21120760

素因数分解:

$2^3\times 5^1\times {\mathrm{409}}^1\times {\mathrm{1291}}^1$

素因数の和:1711

約数の個数: 32

約数和(自身を含む): 47674800

約数和(自身を除く): 26554040

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 409, 818, 1291, 1636, 2045, 2582, 3272, 4090, 5164, 6455, 8180, 10328, 12910, 16360, 25820, 51640, 528019, 1056038, 2112076, 2640095, 4224152, 5280190, 10560380, 21120760]

約数ペア:

[(1, 21120760), (2, 10560380), (4, 5280190), (5, 4224152), (8, 2640095), (10, 2112076), (20, 1056038), (40, 528019), (409, 51640), (818, 25820), (1291, 16360), (1636, 12910), (2045, 10328), (2582, 8180), (3272, 6455), (4090, 5164)]