21991815

素因数分解:

$3^2\times 5^1\times {\mathrm{397}}^1\times {\mathrm{1231}}^1$

素因数の和:1639

約数の個数: 24

約数和(自身を含む): 38246208

約数和(自身を除く): 16254393

約数列:

[1, 3, 5, 9, 15, 45, 397, 1191, 1231, 1985, 3573, 3693, 5955, 6155, 11079, 17865, 18465, 55395, 488707, 1466121, 2443535, 4398363, 7330605, 21991815]

約数ペア:

[(1, 21991815), (3, 7330605), (5, 4398363), (9, 2443535), (15, 1466121), (45, 488707), (397, 55395), (1191, 18465), (1231, 17865), (1985, 11079), (3573, 6155), (3693, 5955)]