19901980

素因数分解:

$2^2\times 5^1\times 7^1\times {\mathrm{142157}}^1$

素因数の和:142173

約数の個数: 24

約数和(自身を含む): 47765088

約数和(自身を除く): 27863108

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 70, 140, 142157, 284314, 568628, 710785, 995099, 1421570, 1990198, 2843140, 3980396, 4975495, 9950990, 19901980]

約数ペア:

[(1, 19901980), (2, 9950990), (4, 4975495), (5, 3980396), (7, 2843140), (10, 1990198), (14, 1421570), (20, 995099), (28, 710785), (35, 568628), (70, 284314), (140, 142157)]