27 (number)

← 26 27 28 →
← 20 21 22 23 24 25 26 27 28 29 → List of numbers — Integers ← 0 10 20 30 40 50 60 70 80 90 →
Cardinal	twenty-seven
Ordinal	27th (twenty-seventh)
Factorization	3^3
Divisors	1, 3, 9, 27
Roman numeral	XXVII
Binary	110112
Ternary	10003
Quaternary	1234
Quinary	1025
Senary	436
Octal	338
Duodecimal	2312
Hexadecimal	1B16
Vigesimal	1720
Base 36	R36

27 (twenty-seven) is the natural number following 26 and preceding 28.

In mathematics

• Twenty-seven is a perfect cube, being 3³ = 3 × 3 × 3. 27 is also ²3 (see tetration). There are exactly 27 straight lines on a smooth cubic surface, which give a basis of the fundamental representation of the E₆ Lie algebra. 27 is also a decagonal number.
• In base 10, it is the first composite number not divisible by any of its digits.
• It is the radix (base) of the septemvigesimal positional numeral system.
• 27 is the only positive integer that is 3 times the sum of its digits.
• In a prime reciprocal magic square of the multiples of 1/7, the magic constant is 27.
• In the Collatz conjecture (aka the "3n + 1 conjecture") a starting value of 27 requires 112 steps to reach 1, many more than any lower number.
• The unique simple formally real Jordan algebra, the exceptional Jordan algebra of self-adjoint 3 by 3 matrices of quaternions, is 27-dimensional.^[1]
• In base 10, it is a Smith number and a Harshad number.
• It is the twenty-eighth (and twenty-ninth) digit in π. (3.141592653589793238462643383279...). If you start counting with 0 it is considered one of few Self-Locating strings in pi.
• 27 contains the decimal digits 2 and 7, and is the result of adding together the integers from 2 to 7 (2 + 3 + 4 + 5 + 6 + 7 = 27)
• There are 27 sporadic groups, if the Tits group is included.

In science

• The atomic number of cobalt.
• The atomic weight of the only stable isotope of aluminum.

Astronomy

• The Messier object M27, a magnitude 7.5 planetary nebula in the constellation Vulpecula, also known as the Dumbbell Nebula.
• The New General Catalogue object NGC 27, a spiral galaxy in the constellation Andromeda
• The Saros number of the solar eclipse series which began on 1993 March and ended on 713 April. The duration of Saros series 27 was 1280.1 years, and it contained 72 solar eclipses. Further, the Saros number of the lunar eclipse series which began on 1944 July and ended on 411 January. The duration of Saros series 27 was 1532.5 years, and it contained 86 lunar eclipses.

Electronics

• The type 27 vacuum tube (valve), a triode introduced in 1927, was the first tube mass-produced for commercial use to incorporate an indirectly heated cathode. This made it the first vacuum tube that could function as a detector in AC-powered radios. Prior to the introduction of the 27, home radios were powered by a set of three or more storage batteries with voltages of 3 volts to 135 volts.

In astrology

• 27 Nakṣatra or lunar mansions in Hindu astrology.

In art

Movies

• Summer, or 27 missing kisses
• Chapter 27-I
• 27 Dresses
• 27 fights
• Order number 27
• Number 27 (written by Michael Palin)

Music

• On Fall Out Boy's album Folie à Deux, there is a song called "27".
• On Passenger's album Whispers, there is also a song called "27".
• On Title Fight's album "Shed", song 10 is titled "27".^[2]
• On Biffy Clyro's album Blackened Sky, there is a song called "27".
• Kim Sung-kyu, South Korean singer, his album name called "27".
• "Weird Al" Yankovic thinks it's a funny number, and it shows up on at least one song in almost every album of his.

References

• Three of the cube is zero (science-fiction story)

Other

• The Minneapolis-based artist Deuce 7 (a.k.a. Deuce Seven, Twenty Seven, 27).

In sports

• The number of outs in a regulation baseball game for each team at all adult levels, including professional play, is 27.
• In auto racing, 27 and 28 were Ferrari Formula one numbers from 1981 to 1995 except in 1990 when reigning WC Alain Prost had the right to use #1 and drove for the team, Nigel Mansell used #2. Popular Canadian driver Gilles Villeneuve used the number on his final days in F1. Later it was adopted by his son Jacques Villeneuve to claim the 1995 CART World Series title, and Canadian IndyCar driver James Hinchcliffe. Jean Alesi, another popular Ferrari driver was the last one ever to use the number back in 1995, also winning the last F1 race with it (as of January 2016), the Canadian GP. Ayrton Senna won his second Formula One World Championship using the mystic number 27 in 1990 in a McLaren Honda, as mentioned, the only time Ferrari didn't use the number during that period. Australian Alan Jones also won the World Drivers Championship in 1980 using number 27 in his Williams.
• As of 2014, Formula 1 drivers selected their career numbers. The # 27, was chosen and is owned by Nico Hülkenberg
• Paul Menard also runs the number 27 in NASCAR as of 2011.
• The jersey number 27 has been retired by several North American sports teams in honor of past playing greats:
  • In Major League Baseball:
    • The Boston Red Sox, for Hall of Famer Carlton Fisk.
    • The Oakland Athletics, for Hall of Famer Catfish Hunter.
    • The San Francisco Giants, for Hall of Famer Juan Marichal.
  • In the NBA:
    • The Cincinnati Royals, for Hall of Famer Jack Twyman. The franchise has continued to honor the number in its later identities—the Kansas City–Omaha Kings, Kansas City Kings, and the current Sacramento Kings.
  • In the NHL:
    • The Phoenix Coyotes, for Teppo Numminen.
    • The Toronto Maple Leafs have a policy of not retiring numbers unless the player honoured either died or suffered a career-ending incident while a member of the team. Other players whose numbers would otherwise be retired instead have their numbers enshrined by the team as "Honoured Numbers", which remain in circulation for future players. The number 27 is currently honoured for Frank Mahovlich and Darryl Sittler.
    • The New Jersey Devils, for Scott Niedermayer
  • No team in the NFL has retired the number.
• The jersey number 27 has also been retired by the softball program of the University of Arizona for pitching great Jennie Finch.

In other fields

Twenty-seven is also:

• The 27 Club is a term used to refer to popular musicians who have died at the age of 27
• A-27 - American attack aircraft
• The total number of letters in the Hebrew alphabet (22 regular letters and 5 final consonants)
• The total number of letters in the Spanish alphabet (5 vowels and 22 consonants)
• The code for international direct-dial phone calls to South Africa
• The name of a cigarette, Marlboro Blend No. 27
• Alternate name for The Hunt, a book by William Diehl
• The number of the French department Eure
• Abbé Faria's prisoner number in the book The Count of Monte Cristo
• One of the anthropomorphic math symbols Lisa Simpson imagines talking to her in The Simpsons episode "Girls Just Want to Have Sums", which, instead of offering the expected pun-based aphorism, rather unhelpfully only says "twenty seven"
• In Stephen King's novel "It", It returns every 27 years to Derry.
• 27 is the number of bones in the human hand.^[3]
• Average crowd funded contribution in the "Bernie Sanders 2016" campaign.

See also

• List of highways numbered 27
• List of highways numbered 27A

References

1. V. G. Kac, "Classification of Simple Z-Graded Lie Superalgebras and Simple Jordan Superalgebras" Communications in Algebra 5 13 (1977): 1380
2. http://titlefightmusic.bandcamp.com/album/shed
3. Steve Jenkins, Bones (2010), ISBN 978-0-545-04651-0

• Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London: Penguin Group. (1987), p. 106.
• Mystery of the number 27 - Large collection of 27 related trivia and facts.
• Prime Curios! 27 from the Prime Pages
• The 27 Project - collection of 27 sightings in movies, TV, culture and art