19721999

素因数分解:

${\mathrm{11}}^1\times {\mathrm{37}}^1\times {\mathrm{47}}^1\times {\mathrm{1031}}^1$

素因数の和:1126

約数の個数: 16

約数和(自身を含む): 22588416

約数和(自身を除く): 2866417

約数列:

[1, 11, 37, 47, 407, 517, 1031, 1739, 11341, 19129, 38147, 48457, 419617, 533027, 1792909, 19721999]

約数ペア:

[(1, 19721999), (11, 1792909), (37, 533027), (47, 419617), (407, 48457), (517, 38147), (1031, 19129), (1739, 11341)]