21128515

素因数分解:

$5^1\times {\mathrm{31}}^1\times {\mathrm{271}}^1\times {\mathrm{503}}^1$

素因数の和:810

約数の個数: 16

約数和(自身を含む): 26320896

約数和(自身を除く): 5192381

約数列:

[1, 5, 31, 155, 271, 503, 1355, 2515, 8401, 15593, 42005, 77965, 136313, 681565, 4225703, 21128515]

約数ペア:

[(1, 21128515), (5, 4225703), (31, 681565), (155, 136313), (271, 77965), (503, 42005), (1355, 15593), (2515, 8401)]