27 (number)
From Wikipedia, the free encyclopedia
27 (twenty-seven) is the natural number following 26 and preceding 28. Twenty-seven is the smallest positive integer requiring four syllables to name in English, though it can be unambiguously defined in just two: "three cubed".
| Cardinal | 27 twenty-seven |
| Ordinal | 27th twenty-seventh |
| Factorization |  |
| Divisors | 1, 3, 9, 27 |
| Roman numeral | XXVII |
| Acrophonic Greek numeral | ΔΔΠΙΙ |
| Alphabetic Greek numeral | κζ´ |
| Hebrew numeral | כז |
| Chinese numeral | 二十七 |
| Financial Chinese numeral | 貳拾柒 |
| Arabic numeral |
٢٧ |
| Binary (2) | 11011 |
| Negabinary (-2) | 1101111 |
| Ternary (3) | 1000 |
| Balanced ternary (-0+) | 1000 |
| Negaternary (-3) | 12000 |
| Quaternary (4) | 123 |
| Quinary (5) | 102 |
| Senary (6) | 43 |
| Septenary (7) | 36 |
| Octal (8) | 33 |
| Nonary (9) | 30 |
| Decimal (10) | 27 |
| Undecimal (11) | 25 |
| Duodecimal (12) | 23 |
| Tridecimal (13) | 21 |
| Hexadecimal (16) | 1B |
| Vigesimal (20) | 17 |
| Quadrovigesimal (24) | 13 |
| Septemvigesimal (27) | 10 |
| Trigesimal (30) | R |
| Hexatridecimal (36) | R |
| Phinary (φ) | 1010010.010101 111101.10111111 |
Contents |
[edit] In mathematics
Twenty-seven is a perfect cube, being 33 = 3 × 3 × 3. 27 is 3↑↑2 (using Knuth's up-arrow notation). There are exactly 27 straight lines on a cubic surface. 27 is also a decagonal number.
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. It is the twenty-eighth (and twenty-ninth) digit in π. (3.141592653589793238462643383279...).
In base 10, it is a Smith number and a Harshad number.
The unique simple formally real Jordan algebra, the exceptional Jordan algebra of self-adjoint 3 by 3 matrices of quaternions, is 27-dimensional.
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.
It's the cube root of 19,683.
[edit] In science
- The atomic number of cobalt.
[edit] 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 9 and ended on -713 April 16. 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 17 and ended on -411 January 23. The duration of Saros series 27 was 1532.5 years, and it contained 86 lunar eclipses.
- The 27th moon of Jupiter is Sinope.
[edit] In religion
- There are a total of 27 books in the New Testament
[edit] In music
- The number of completed, numbered piano concertos by Wolfgang Amadeus Mozart
- The age in years at which many famous rock musicians died, sometimes referred to as the 27 Club. Occasionally, this is termed the "ideal" age to die, and the concept has inspired a brand of clothing, DeadAt27
- A number which American parodist "Weird Al" Yankovic hides somewhere in many of his songs and videos here
- The name of the second track on, and first single released from, the Biffy Clyro album Blackened Sky
- The number of "8 by 10 color glossy photographs with circles and arrows" in the song Alice's Restaurant by Arlo Guthrie
- In the song "The Ex" by Billy Talent off of their self-titled album, Ben says "So i sat in my room for 27 days, no she never called, i had something to say"
[edit] In other fields
Twenty-seven is also:
- The total number of letters in the Hebrew alphabet (22 regular letters and 5 final consonants)
- The number of letters in the Spanish alphabet
- Rusty Wallace's car number when he won the 1989 NASCAR Winston Cup championship.
- The number most commonly associated with F1 driver Gilles Villeneuve
- The current number of Amendments to the United States Constitution.
- The modal age of the peak peformance year for major league baseball position players, according to a commonly accepted theory by sabermetrician Bill James
- The code for international direct-dial phone calls to South Africa
- With the number 37, a key number in comedian Charles Fleischer's concept of moleeds
- The designation (I-27) of a US interstate highway in Texas
- The designation (US 27) of a United States national highway from Fort Wayne, Indiana to Miami, Florida
- The name of a popular cigarette, Marlboro Blend No. 27
- The number of books in the first Xanth "trilogy"
- The number of outs in a regulation Professional baseball game.
- "The Bankers Case" on the U.S. Version of Deal or No Deal
[edit] Historical years
27 A.D., 27 B.C., 1927, 2027, etc.
