Primes / Is 317 prime?

Is 317 a Prime Number?

Yes

317 is prime: for 317, testing every prime up to √317 ≈ 17.8 (namely 2, 3, 5, 7, 11, 13, 17) finds no divisor. 317 sits between primes 313 and 331, 4 below and 14 above. 317 shares no factor with 2-12; 317's divisors start beyond that range. 317 is odd, digit sum 11 for 317, digital root 2 for 317. 317 has 4 primes within 10 of 317.