27 (number)

← 26
28 →
27
Cardinal twenty-seven
Ordinal 27th
(twenty-seventh)
Factorization 3^3
Divisors 1, 3, 9, 27
Roman numeral XXVII
Binary 110112
Octal 338
Duodecimal 2312
Hexadecimal 1B16

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

Contents

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.

27 has an aliquot sum of 13 and is the first composite member of the 13-aliquot tree with the aliquot sequence (27,13,1,0). Twenty-seven is the aliquot sum of the two odd discrete semiprimes 69 and 133.

273 = 19,683 and 1+9+6+8+3=27.

In base 10, it is the first composite number not evenly divisible by any of its digits. It is the radix (base) of the septemvigesimal positional numeral system.

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 contain numbers 2 and 7 if you take line of numbers starting with 2 ending with 7 you will get 27 in result. (2+3+4+5+6+7=27)

In science

Astronomy

Electronics

In religion, philosophy and the occult

In astrology

In politics

In music

Many talented and famous rock/blues musicians died at age 27. These include Robert Johnson, Brian Jones, Jimi Hendrix, Janis Joplin, Jim Morrison, Ron McKernan, Kurt Cobain, and Amy Winehouse. The musicians who died at this age are often referred to as the 27 Club.

There are many songs titled just "Twenty-Seven," so it will suffice to list the most famous: a song by Scottish band Biffy Clyro from their 2002 album, Blackened Sky; the song by the Dave Matthews Band "#27," which they began playing on their 2007 summer tour; the Lagwagon song on their album Double Plaidinum. A song by rock band Fall Out Boy also bears the title "27," and is on their 2008 album Folie a Deux.

An Atlanta based pop/punk band named Cartel also has a song titled "27 Steps" in their 2009 album Cycles.

The number also occurs buried in the lyrics without occurring in the title. American parodist "Weird Al" Yankovic hides the number in many of his songs and videos.[2] Ben Weasel also likes to include the number in his songs for his bands Screeching Weasel and The Riverdales.

In the United States, the number 27 is associated with the East Bay punk scene. There is also a band from Boston simply called 27.

Sector 27 is a rock band founded by Tom Robinson.

Level 27 Clothing is a brand started by Billy Martin, guitarist for pop-punk band Good Charlotte.

Wolfgang Mozart composed 27 concertos for pianoforte and orchestra.

Punk rock outfit Title Fight has a song titled 27.

The band Pinhead Gunpowder also has a song titled 27.

In art

movies:

References:

other

In sports

In other fields

Twenty-seven is also:

Historical years

27 B.C., 27 A.D., 1827, 1927, 2027, etc.

References

  1. ^ V. G. Kac, "Classification of Simple Z-Graded Lie Superalgebras and Simple Jordan Superalgebras" Communications in Algebra 5 13 (1977): 1380
  2. ^ Thread from the Weird Al forum
  3. ^ Steve Jenkins, Bones (2010), ISBN 9780545046510
  4. ^ Leonardo's Notebooks by Leonardo da Vinci, edited by H. Anna Suh (2005), ISBN 1579125222.