21019985

素因数分解:

$5^1\times 7^1\times {\mathrm{19}}^1\times {\mathrm{73}}^1\times {\mathrm{433}}^1$

素因数の和:537

約数の個数: 32

約数和(自身を含む): 30831360

約数和(自身を除く): 9811375

約数列:

[1, 5, 7, 19, 35, 73, 95, 133, 365, 433, 511, 665, 1387, 2165, 2555, 3031, 6935, 8227, 9709, 15155, 31609, 41135, 48545, 57589, 158045, 221263, 287945, 600571, 1106315, 3002855, 4203997, 21019985]

約数ペア:

[(1, 21019985), (5, 4203997), (7, 3002855), (19, 1106315), (35, 600571), (73, 287945), (95, 221263), (133, 158045), (365, 57589), (433, 48545), (511, 41135), (665, 31609), (1387, 15155), (2165, 9709), (2555, 8227), (3031, 6935)]