21380980

素因数分解:

$2^2\times 5^1\times {\mathrm{139}}^1\times {\mathrm{7691}}^1$

素因数の和:7839

約数の個数: 24

約数和(自身を含む): 45228960

約数和(自身を除く): 23847980

約数列:

[1, 2, 4, 5, 10, 20, 139, 278, 556, 695, 1390, 2780, 7691, 15382, 30764, 38455, 76910, 153820, 1069049, 2138098, 4276196, 5345245, 10690490, 21380980]

約数ペア:

[(1, 21380980), (2, 10690490), (4, 5345245), (5, 4276196), (10, 2138098), (20, 1069049), (139, 153820), (278, 76910), (556, 38455), (695, 30764), (1390, 15382), (2780, 7691)]