Factors / Factors of 191

Factors of 191

1, 191

191 is prime: only factor pair is (1, 191), confirmed by trial division up to √191 ≈ 13.8 turning up nothing else. 191's full pair list is (1, 191), for 2 divisors in total. 191's divisors other than 191 itself sum to just 1, 190 below 191: the common deficient case. 191 is odd, digit sum 11 for 191; none of 2-12 divide 191 evenly. 191 has 2 divisors; 190 has 8 and 192 has 14, so 192 wins here. 191 divided by its largest divisor, 1, gives 191.