20991428

素因数分解:

$2^2\times {\mathrm{19}}^2\times {\mathrm{14537}}^1$

素因数の和:14579

約数の個数: 18

約数和(自身を含む): 38772846

約数和(自身を除く): 17781418

約数列:

[1, 2, 4, 19, 38, 76, 361, 722, 1444, 14537, 29074, 58148, 276203, 552406, 1104812, 5247857, 10495714, 20991428]

約数ペア:

[(1, 20991428), (2, 10495714), (4, 5247857), (19, 1104812), (38, 552406), (76, 276203), (361, 58148), (722, 29074), (1444, 14537)]