Factors / Factors of 40

Factors of 40

1, 2, 4, 5, 8, 10, 20, 40

40 breaks into 4 pairs, tested up to √40 ≈ 6.3; each pair multiplies back to 40 exactly. 40's full pair list is (1, 40), (2, 20), (4, 10), (5, 8), for 8 divisors in total. 40's divisors other than 40 itself sum to 50, 10 above 40: abundant. 40 is even, digit sum 4 for 40; small divisors of 40 include 2, 4, 5, 8, 10. 40 has 8 divisors; 39 has 4 and 41 has 2, so 40 wins here. 40 divided by its largest divisor, 20, gives 2.