6 is the second smallest composite number.[1] It is also the first number that is the sum of its proper divisors, making it the smallest perfect number.[2] 6 is the first unitary perfect number, since it is the sum of its positive proper unitary divisors, without including itself. Only five such numbers are known to exist.[3] 6 is the largest of the four all-Harshad numbers.[4]
Sexy prime pairs – Prime pairs differing by six are sexy, because sex is the Latin word for six.[17][18]
The SI prefix for 10006 is exa- (E), and for its reciprocal atto- (a).
Evolution of the Hindu-Arabic digit
The evolution of our modern digit 6 appears rather simple when compared with the other digits. The modern 6 can be traced back to the Brahmi numerals of India, which are first known from the Edicts of Ashoka c. 250 BCE.[19][20][21][22] It was written in one stroke like a cursive lowercase e rotated 90 degrees clockwise. Gradually, the upper part of the stroke (above the central squiggle) became more curved, while the lower part of the stroke (below the central squiggle) became straighter. The Arabs dropped the part of the stroke below the squiggle. From there, the European evolution to our modern 6 was very straightforward, aside from a flirtation with a glyph that looked more like an uppercase G.[23]
On the seven-segment displays of calculators and watches, 6 is usually written with six segments. Some historical calculator models use just five segments for the 6, by omitting the top horizontal bar. This glyph variant has not caught on; for calculators that can display results in hexadecimal, a 6 that looks like a "b" is not practical.
Just as in most modern typefaces, in typefaces with text figures the character for the digit 6 usually has an ascender, as, for example, in .[24]
This digit resembles an inverted 9. To disambiguate the two on objects and documents that can be inverted, the 6 has often been underlined, both in handwriting and on printed labels.
Most woodwind instruments have six basic holes or keys (e.g., bassoon, clarinet, pennywhistle, saxophone); these holes or keys are usually not given numbers or letters in the fingering charts
The theme of the sixth album by Dream Theater, Six Degrees of Inner Turbulence, was the number six: the album has six songs, and the sixth song—that is, the complete second disc—explores the stories of six individuals suffering from various mental illnesses.[36]
Aristotle gave six elements of tragedy, the first of which is Mythos.[37]
Note 1: The word day is not always used in the Quran to mean a 24-hour period. According to Surah Al-Hajj (The Pilgrimage):47, a heavenly Day is 1000 years of our time. The Day of Judgment will be 50,000 years of our time - Surah Al-Maarij (The Ascending Stairways):4. Hence, the six Days of creation refer to six eons of time, known only by Allah.
Note 2: Some Islamic scholars believe this verse comes in response to Exodus 31:17, which says, "The Lord made the heavens and the earth in six days, but on the seventh day He rested and was refreshed."
The six elements most common in biomolecules are called the CHNOPS elements; the letters stand for the chemical abbreviations of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. See CHON.[53]
Chemistry
A benzene molecule has a ring of six carbon atoms.[54]
The p-orbital allows an element to bind up to a maximum of six electrons.
Medicine
There are six tastes in traditional Indian medicine (Ayurveda): sweet, sour, salty, bitter, pungent, and astringent. These tastes are used to suggest a diet based on the symptoms of the body.[57]
On most phones, the 6 key is associated with the letters M, N, and O, but on the BlackBerry Pearl it is the key for J and K, and on the BlackBerry 8700 series and Curve 8900 with full keyboard, it is the key for F
^Weisstein, Eric W. "Six Exponentials Theorem". mathworld.wolfram.com. Retrieved 2020-08-03.
^Weisstein, Eric W. "Kissing Number". mathworld.wolfram.com. Retrieved 2020-08-03.
^Griess, Jr., Robert L. (1982). "The Friendly Giant" (PDF). Inventiones Mathematicae. 69: 91–96. Bibcode:1982InMat..69....1G. doi:10.1007/BF01389186. hdl:2027.42/46608. MR 0671653. S2CID 123597150. Zbl 0498.20013.
^Weisstein, Eric W. "Hexadecimal". mathworld.wolfram.com. Retrieved 2020-08-03.
^Weisstein, Eric W. "Hexagon". mathworld.wolfram.com. Retrieved 2020-08-03.
^Weisstein, Eric W. "Hexahedron". mathworld.wolfram.com. Retrieved 2020-08-03.
^Weisstein, Eric W. "Base". mathworld.wolfram.com. Retrieved 2020-08-03.
^Chris K. Caldwell; G. L. Honaker Jr. (2009). Prime Curios!: The Dictionary of Prime Number Trivia. CreateSpace Independent Publishing Platform. p. 11. ISBN 978-1-4486-5170-2.
^Weisstein, Eric W. "Sexy Primes". mathworld.wolfram.com. Retrieved 2020-08-03.
^Hollingdale, Stuart (2014). Makers of Mathematics. Courier Corporation. pp. 95–96. ISBN 978-0-486-17450-1.
^Publishing, Britannica Educational (2009). The Britannica Guide to Theories and Ideas That Changed the Modern World. Britannica Educational Publishing. p. 64. ISBN 978-1-61530-063-1.
^Katz, Victor J.; Parshall, Karen Hunger (2014). Taming the Unknown: A History of Algebra from Antiquity to the Early Twentieth Century. Princeton University Press. p. 105. ISBN 978-1-4008-5052-5.
^Pillis, John de (2002). 777 Mathematical Conversation Starters. MAA. p. 286. ISBN 978-0-88385-540-9.
^Georges Ifrah, The Universal History of Numbers: From Prehistory to the Invention of the Computer transl. David Bellos et al. London: The Harvill Press (1998): 395, Fig. 24.66
^Negru, John (1988). Computer Typesetting. Van Nostrand Reinhold. p. 59. ISBN 978-0-442-26696-7. slight ascenders that rise above the cap height ( in 4 and 6 )
^Auric, Georges; Durey, Louis; Honegger, Arthur; Milhaud, Darius; Poulenc, Francis; Tailleferre, Germaine (2014-08-20). Caramel Mou and Other Great Piano Works of "Les Six": Pieces by Auric, Durey, Honegger, Milhaud, Poulenc and Tailleferre (in French). Courier Corporation. ISBN 978-0-486-49340-4.
^"Six Organs of Admittance". www.sixorgans.com. Retrieved 2020-08-03.
^"Electric Six | Biography, Albums, Streaming Links". AllMusic. Retrieved 2020-08-03.
^"Sixpence None The Richer". GRAMMY.com. 2020-05-19. Retrieved 2020-08-04.
^"You Me at Six | Biography & History". AllMusic. Retrieved 2020-08-04.
^"Definition of GUITAR". www.merriam-webster.com. Retrieved 2020-08-04.
^D'Amante, Elvo (1994-01-01). Music Fundamentals: Pitch Structures and Rhythmic Design. Scarecrow Press. p. 194. ISBN 978-1-4616-6985-2. The division of an octave into six equal parts is referred to as the whole-tone scale
^Horsley, Charles Edward (1876). A Text Book of Harmony: For the Use of Schools and Students. Sampson Low, Marston, Searle, & Rivington. p. 4. Like the Tritone, it contains six semitones
^Tribble, Mimi (2004). 300 Ways to Make the Best Christmas Ever!: Decorations, Carols, Crafts & Recipes for Every Kind of Christmas Tradition. Sterling Publishing Company, Inc. p. 145. ISBN 978-1-4027-1685-0. Six geese a-laying
^Staines, Joe (2010-05-17). The Rough Guide to Classical Music. Penguin. p. 393. ISBN 978-1-4053-8321-9. ...the six arias with variations collected under the title Hexachordum Apollinis (1699)...
^Hegarty, Paul; Halliwell, Martin (2011-06-23). Beyond and Before: Progressive Rock since the 1960s. Bloomsbury Publishing USA. p. 169. ISBN 978-1-4411-1480-8. Six Degrees of Inner Turbulence
^Curran, Angela (2015-10-05). Routledge Philosophy Guidebook to Aristotle and the Poetics. Routledge. p. 133. ISBN 978-1-317-67706-2. THE SIX QUALITATIVE ELEMENTS OF TRAGEDY
^Plaut, W. Gunther (1991). The Magen David: How the Six-pointed Star Became an Emblem for the Jewish People. B'nai B'rith Books. ISBN 978-0-910250-16-0. How the Six-pointed Star Became an Emblem for the Jewish People
^Lauterbach, Jacob Zallel (1916). Midrash and Mishnah: A Study in the Early History of the Halakah. Bloch. p. 9. Six orders of Mishnah
^Rosen, Ceil; Rosen, Moishe (2006-05-01). Christ in the Passover. Moody Publishers. p. 79. ISBN 978-1-57567-480-3. Six symbolic foods
^Repcheck, Jack (2008-12-15). The Man Who Found Time: James Hutton And The Discovery Of Earth's Antiquity. Basic Books. ISBN 978-0-7867-4399-5. it actually took only six days to create the earth
^"CHURCH FATHERS: City of God, Book XI (St. Augustine)". www.newadvent.org. Retrieved 2020-08-04. These works are recorded to have been completed in six days (the same day being six times repeated), because six is a perfect number
^Grossman, Grace Cohen; Ahlborn, Richard E.; Institution, Smithsonian (1997). Judaica at the Smithsonian: Cultural Politics as Cultural Model. Smithsonian Institution Press. p. 228. Shavuot falls on the sixth day of the Hebrew month of Sivan
^Robertson, William Archibald Scott (1880). The crypt of Canterbury cathedral; its architecture, its history, and its frescoes. Mitchell & Hughes. p. 91. ...but seraphs, with six wings
^Shapera, Paul M. (2009-08-15). Iran's Religious Leaders. The Rosen Publishing Group, Inc. p. 10. ISBN 978-1-4358-5283-9. Islam has six articles of faith
^Algül, Hüseyin (2005). The Blessed Days and Nights of the Islamic Year. Tughra Books. p. 65. ISBN 978-1-932099-93-5. ...it was blessed to fast for six days in the month of Shawwal...
^Bary, William Theodore De; DeBary, William T.; Chan, Wing-tsit; Lufrano, Richard; Ching, Julia; Johnson, David; Liu, Kwang-Ching; Mungello, David (1999). Sources of Chinese Tradition. Columbia University Press. ISBN 978-0-231-11270-3. ...and the Six Ministries were made...
^Rhoads, Samuel E. (1996). The Sky Tonight: A Guided Tour of the Stars Over Hawaiʻi. Bishop Museum Press. ISBN 978-0-930897-93-2. Three Messier objects are visible in this part of the sky : M6, M7 and M8 .
^Sedgwick, Marcus (2011-07-05). White Crow. Roaring Brook Press. p. 145. ISBN 978-1-4299-7634-3. The cells of honeycombs are six-sided because a hexagon is the most material-efficient tessellation
^Parker, Steve (2005). Ant Lions, Wasps & Other Insects. Capstone. p. 16. ISBN 978-0-7565-1250-7. Insects have six legs each...
^Pendarvis, Murray P.; Crawley, John L. (2019-02-01). Exploring Biology in the Laboratory: Core Concepts. Morton Publishing Company. p. 10. ISBN 978-1-61731-899-3. ...presently at least six kingdoms are recognized;
^Mader, Sylvia S. (2004). Biology. McGraw-Hill. p. 20. ISBN 978-0-07-291934-9. The acronym CHNOPS helps us remember these six elements
^Dufour, Fritz (2018-09-19). The Realities of Reality - Part II: Making Sense of Why Modern Science Advances. Vol. 1. Fritz Dufour. p. 100. The benzene molecule has its six carbon atoms in a ring[self-published source?]
^Starr, Cecie; Evers, Christine (2012-05-10). Biology Today and Tomorrow without Physiology. Cengage Learning. p. 25. ISBN 978-1-133-36536-5. For example, the atomic number of carbon is 6,
^Webb, Stephen; Webb, Professor of Australian Studies Stephen (2004-05-25). Out of this World: Colliding Universes, Branes, Strings, and Other Wild Ideas of Modern Physics. Springer Science & Business Media. p. 16. ISBN 978-0-387-02930-6. snowflake, with its familiar sixfold rotational symmetry
^Woo, Teri Moser; Robinson, Marylou V. (2015-08-03). Pharmacotherapeutics For Advanced Practice Nurse Prescribers. F.A. Davis. p. 145. ISBN 978-0-8036-4581-3. Ayurvedic herbology is based on the tridoshic theory that there exist six basic tastes
^Pandemic Influenza Preparedness and Response Guidance for Healthcare Workers and Healthcare Employers. OSHA, U.S. Department of Labor. 2007. p. 8. The WHO Plan describes six phases of increasing public health risk associated with the emergence of a new influenza
^Sanghera, Paul (2011-03-08). Quantum Physics for Scientists and Technologists: Fundamental Principles and Applications for Biologists, Chemists, Computer Scientists, and Nanotechnologists. John Wiley & Sons. p. 64. ISBN 978-0-470-92269-9. ...there are six types of quarks and six types of leptons.
^Jimbo, M.; Jimbo, Michio; Miwa, Tetsuji; Tsuchiya, Akihiro (1989). Integrable Systems in Quantum Field Theory and Statistical Mechanics. Academic Press. p. 588. ISBN 978-0-12-385342-4. Allowed configurations in the six-vertex model and their statistical weights
^Sloan, Robin James Stuart (2015-05-07). Virtual Character Design for Games and Interactive Media. CRC Press. p. 34. ISBN 978-1-4665-9820-1. placing six primaries around the wheel in the following order: red, yellow, green, cyan, blue, magenta.
^Stevens, E. S. (2002). Green Plastics: An Introduction to the New Science of Biodegradable Plastics. Princeton University Press. p. 45. ISBN 978-0-691-04967-0.
^Bunson, Matthew (2014-05-14). Encyclopedia of the Roman Empire. Infobase Publishing. p. 90. ISBN 978-1-4381-1027-1. Augustus was also originally called Sextilis, the sixth month.
^Nicolas, Sir Nicholas Harris (1833). The Chronology of History: Containing Tables, Calculations and Statements, Indispensable for Ascertaining the Dates of Historical Events and of Public and Private Documents from the Earliest Period to the Present Time. Longham, Rees, Orme, Brown, Green, & Longman and John Taylor. p. 172. SEXTIDI, or " Jour de la Révolution, "
^Rimes, Wendy (2016-04-01). "The Reason Why The Dead Are Buried Six Feet Below The Ground". Elite Readers. Retrieved 2020-08-06.
^"Six Degrees of Peggy Bacon". www.aaa.si.edu. 27 June 2012. Retrieved 2020-08-06.
^"Virgo | constellation and astrological sign". Encyclopedia Britannica. Retrieved 2020-08-06.
^Wilkinson, Endymion Porter; Wilkinson, Scholar and Diplomat (Eu Ambassador to China 1994-2001) Endymion (2000). Chinese History: A Manual. Harvard Univ Asia Center. p. 11. ISBN 978-0-674-00249-4.{{cite book}}: CS1 maint: numeric names: authors list (link)
^Peirce, Gareth (2011-03-12). "The Birmingham Six: Have we learned from our disgraceful past?". The Guardian. ISSN 0261-3077. Retrieved 2020-08-06.
^Smith, Michael (2011-10-31). Six: The Real James Bonds 1909-1939. Biteback Publishing. ISBN 978-1-84954-264-7.
The Odd Number 6, JA Todd, Math. Proc. Camb. Phil. Soc. 41 (1945) 66–68
A Property of the Number Six, Chapter 6, P Cameron, JH v. Lint, Designs, Graphs, Codes and their Links ISBN 0-521-42385-6
Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London: Penguin Group. (1987): 67 - 69