300 (number) nontotient. 315 = 3 × 5 × 7. 315 is a Harshad number 316 = 2 × 79. 316 is a centered triangular number and a centered heptagonal number 317 is a prime number, Eisenstein prime with no imaginary part, Chen prime, and a strictly non-palindromic number. 317 is also shorthand for the LM317 adjustable regulator chip. It is also the area code for the Indianapolis region. 318 = 2 × 3 × 53. It is a sphenic number, nontotient, and the sum of twelve consecutive primes (7 + 11 + 13 + 17 + 19 + 23 + 29
Largest known prime number Largest known prime number The largest known prime number () is 2 − 1, a number with 23,249,425 digits. It was found by the Great Internet Mersenne Prime Search (GIMPS) in 2017. Euclid proved that there is no largest prime number, and many mathematicians and hobbyists continue to search for large prime numbers. Many of the largest known primes are Mersenne primes. , the seven largest known primes are Mersenne primes. The last sixteen record primes were Mersenne primes. The fast Fourier transform implementation of the Lucas–Lehmer primality test for Mersenne numbers is fast compared to other known primality tests