21320405

素因数分解:

$5^1\times {\mathrm{31}}^1\times {\mathrm{67}}^1\times {\mathrm{2053}}^1$

素因数の和:2156

約数の個数: 16

約数和(自身を含む): 26817024

約数和(自身を除く): 5496619

約数列:

[1, 5, 31, 67, 155, 335, 2053, 2077, 10265, 10385, 63643, 137551, 318215, 687755, 4264081, 21320405]

約数ペア:

[(1, 21320405), (5, 4264081), (31, 687755), (67, 318215), (155, 137551), (335, 63643), (2053, 10385), (2077, 10265)]