71 (number)
From Wikipedia, the free encyclopedia
71 (seventy-one) is the natural number following 70 and preceding 72.
| Cardinal | 71 seventy-one |
| Ordinal | 71st seventy-first |
| Factorization | prime |
| Divisors | 1, 71 |
| Roman numeral | LXXI |
| Binary | 1000111 |
| Hexadecimal | 47 |
[edit] In mathematics
It is the 20th prime number. The next is 73, with which it composes a twin prime. It is also a permutable prime with 17. If we add up the primes less than 71 (2 through 67), we get 568, which is divisible by 71, 8 times. 71 is the largest supersingular prime. Also, 712 = 7! + 1, making it part of the last known pair of Brown numbers, as (71, 7). It is an Eisenstein prime with no imaginary part and real part of the form 3n − 1. Since 9! + 1 is divisible by 71 but 71 is not one more than a multiple of 9, 71 is a Pillai prime.
71 is a centered heptagonal number.
[edit] In science
- The atomic number of lutetium, a lanthanide
In astronomy,
- Messier object M71, a magnitude 8.5 globular cluster in the constellation Sagitta
- The New General Catalogue object NGC 71, a magnitude 13.2 peculiar spiral galaxy in the constellation Andromeda
- The Saros number of the solar eclipse series which began on -702 October 8 and ended on 777 March 14. The duration of Saros series 71 was 1478.4 years, and it contained 83 solar eclipses.
- The Saros number of the lunar eclipse series which began on -472 June 4 and ended on 808 July 11. The duration of Saros series 71 was 1280.1 years, and it contained 72 lunar eclipses.
[edit] In other fields
Seventy-one is also:
- The designation of USA Interstate 71, which runs from Kentucky to Ohio.
- The registry of the U.S. Navy's nuclear aircraft carrier USS Theodore Roosevelt (CVN-71), named after U.S. President Theodore Roosevelt.
- The number of the French department Saône-et-Loire.
- The year AD 71, 71 BC, or 1971.
- In the Mexican television sitcom, El Chavo del Ocho, Doña Clotilde lives in the apartment number 71, being therefore known as "Bruja del 71" (Witch of 71).
- Affiliated with visual artist, DJ, and record producer Odd Nosdam
- The best-known car number of NASCAR legend Dave Marcis.
