21315555

素因数分解:

$3^4\times 5^1\times {\mathrm{52631}}^1$

素因数の和:52648

約数の個数: 20

約数和(自身を含む): 38210832

約数和(自身を除く): 16895277

約数列:

[1, 3, 5, 9, 15, 27, 45, 81, 135, 405, 52631, 157893, 263155, 473679, 789465, 1421037, 2368395, 4263111, 7105185, 21315555]

約数ペア:

[(1, 21315555), (3, 7105185), (5, 4263111), (9, 2368395), (15, 1421037), (27, 789465), (45, 473679), (81, 263155), (135, 157893), (405, 52631)]