Primes / Is 109 prime?

Is 109 a Prime Number?

Yes

109 is prime: for 109, testing every prime up to √109 ≈ 10.4 (namely 2, 3, 5, 7) finds no divisor. 109 sits between primes 107 and 113, 2 below and 4 above. 109 shares no factor with 2-12; 109's divisors start beyond that range. 109 is odd, digit sum 10 for 109, digital root 1 for 109. 109 has 5 primes within 10 of 109.