21581080

素因数分解:

$2^3\times 5^1\times {\mathrm{211}}^1\times {\mathrm{2557}}^1$

素因数の和:2779

約数の個数: 32

約数和(自身を含む): 48806640

約数和(自身を除く): 27225560

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 211, 422, 844, 1055, 1688, 2110, 2557, 4220, 5114, 8440, 10228, 12785, 20456, 25570, 51140, 102280, 539527, 1079054, 2158108, 2697635, 4316216, 5395270, 10790540, 21581080]

約数ペア:

[(1, 21581080), (2, 10790540), (4, 5395270), (5, 4316216), (8, 2697635), (10, 2158108), (20, 1079054), (40, 539527), (211, 102280), (422, 51140), (844, 25570), (1055, 20456), (1688, 12785), (2110, 10228), (2557, 8440), (4220, 5114)]