19998380

素因数分解:

$2^2\times 5^1\times {\mathrm{991}}^1\times {\mathrm{1009}}^1$

素因数の和:2009

約数の個数: 24

約数和(自身を含む): 42080640

約数和(自身を除く): 22082260

約数列:

[1, 2, 4, 5, 10, 20, 991, 1009, 1982, 2018, 3964, 4036, 4955, 5045, 9910, 10090, 19820, 20180, 999919, 1999838, 3999676, 4999595, 9999190, 19998380]

約数ペア:

[(1, 19998380), (2, 9999190), (4, 4999595), (5, 3999676), (10, 1999838), (20, 999919), (991, 20180), (1009, 19820), (1982, 10090), (2018, 9910), (3964, 5045), (4036, 4955)]