41 (number)
41 is the natural number following 40 and preceding 42.
| |||
| Cardinal | forty-one | ||
| Ordinal | 41st(forty-first) | ||
| Factorization | prime | ||
| Roman numeral | XLI | ||
| Binary | 101001 | ||
| Hexadecimal | 29 | ||
Forty-one is the 13th smallest prime number. The next is forty-three, with which it comprises a twin prime. Forty-one is also a Sophie Germain prime and a Newman-Shanks-Williams prime.
The number figures in the polynomial f(n) = n2 + n + 41, which yields primes for 0 <= n < 40.
Forty-one is the sum of two squares, 42 + 52, as well as the sum of the first six prime numbers, and also the sum of three primes (11 + 13 + 17). It is a centered square number.
Forty-one is also:
- the atomic number of niobium.
- the model number of the HP-41C/CV/CX
- in A Thousand and One Nights, the number of thieves accompanying Ali Baba.
- a number 'encoded' in a lot of the music of Johann Sebastian Bach. Bach may have considered this number a sort of signature, since given A = 1, B = 2, C = 3, etc., then B + A + C + H = 14 and J + S + B + A + C + H = 41.
- the code for direct dial international phone calls to Switzerland.
- The year A.D. 41, 41 BC, or 1941.
- #41 is a song by Dave Matthews Band.
- C-41 is the film developing process for 35mm color negative film.