Factors / Factors of 511

Factors of 511

1, 7, 73, 511

511 breaks into 2 pairs, tested up to √511 ≈ 22.6; each pair multiplies back to 511 exactly. 511's full pair list is (1, 511), (7, 73), for 4 divisors in total. 511's divisors other than 511 itself sum to just 81, 430 below 511: the common deficient case. 511 is odd, digit sum 7 for 511; small divisors of 511 include 7. 511 has 4 divisors; 510 has 16 and 512 has 10, so 510 wins here. 511 divided by its largest divisor, 73, gives 7.