21128540

素因数分解:

$2^2\times 5^1\times {\mathrm{97}}^1\times {\mathrm{10891}}^1$

素因数の和:10997

約数の個数: 24

約数和(自身を含む): 44831472

約数和(自身を除く): 23702932

約数列:

[1, 2, 4, 5, 10, 20, 97, 194, 388, 485, 970, 1940, 10891, 21782, 43564, 54455, 108910, 217820, 1056427, 2112854, 4225708, 5282135, 10564270, 21128540]

約数ペア:

[(1, 21128540), (2, 10564270), (4, 5282135), (5, 4225708), (10, 2112854), (20, 1056427), (97, 217820), (194, 108910), (388, 54455), (485, 43564), (970, 21782), (1940, 10891)]