Primes / Is 11 prime?

Is 11 a Prime Number?

Yes

11 is prime: for 11, testing every prime up to √11 ≈ 3.3 (namely 2, 3) finds no divisor. 11 sits between primes 7 and 13, 4 below and 2 above. 11 shares no factor with 2-12; 11's divisors start beyond that range. 11 is odd, digit sum 2 for 11, digital root 2 for 11. 11 has 8 primes within 10 of 11.