21128875

素因数分解:

$5^3\times {\mathrm{17}}^1\times {\mathrm{61}}^1\times {\mathrm{163}}^1$

素因数の和:256

約数の個数: 32

約数和(自身を含む): 28551744

約数和(自身を除く): 7422869

約数列:

[1, 5, 17, 25, 61, 85, 125, 163, 305, 425, 815, 1037, 1525, 2125, 2771, 4075, 5185, 7625, 9943, 13855, 20375, 25925, 49715, 69275, 129625, 169031, 248575, 346375, 845155, 1242875, 4225775, 21128875]

約数ペア:

[(1, 21128875), (5, 4225775), (17, 1242875), (25, 845155), (61, 346375), (85, 248575), (125, 169031), (163, 129625), (305, 69275), (425, 49715), (815, 25925), (1037, 20375), (1525, 13855), (2125, 9943), (2771, 7625), (4075, 5185)]