Factors / Factors of 257

Factors of 257

1, 257

257 is prime: only factor pair is (1, 257), confirmed by trial division up to √257 ≈ 16.0 turning up nothing else. 257's full pair list is (1, 257), for 2 divisors in total. 257's divisors other than 257 itself sum to just 1, 256 below 257: the common deficient case. 257 is odd, digit sum 14 for 257; none of 2-12 divide 257 evenly. 257 has 2 divisors; 256 has 9 and 258 has 8, so 256 wins here. 257 divided by its largest divisor, 1, gives 257.