21491275

素因数分解:

$5^2\times {\mathrm{13}}^1\times {\mathrm{89}}^1\times {\mathrm{743}}^1$

素因数の和:855

約数の個数: 24

約数和(自身を含む): 29060640

約数和(自身を除く): 7569365

約数列:

[1, 5, 13, 25, 65, 89, 325, 445, 743, 1157, 2225, 3715, 5785, 9659, 18575, 28925, 48295, 66127, 241475, 330635, 859651, 1653175, 4298255, 21491275]

約数ペア:

[(1, 21491275), (5, 4298255), (13, 1653175), (25, 859651), (65, 330635), (89, 241475), (325, 66127), (445, 48295), (743, 28925), (1157, 18575), (2225, 9659), (3715, 5785)]