21781565

素因数分解:

$5^1\times {\mathrm{13}}^2\times {\mathrm{149}}^1\times {\mathrm{173}}^1$

素因数の和:353

約数の個数: 24

約数和(自身を含む): 28657800

約数和(自身を除く): 6876235

約数列:

[1, 5, 13, 65, 149, 169, 173, 745, 845, 865, 1937, 2249, 9685, 11245, 25181, 25777, 29237, 125905, 128885, 146185, 335101, 1675505, 4356313, 21781565]

約数ペア:

[(1, 21781565), (5, 4356313), (13, 1675505), (65, 335101), (149, 146185), (169, 128885), (173, 125905), (745, 29237), (845, 25777), (865, 25181), (1937, 11245), (2249, 9685)]