21281991

素因数分解:

$3^1\times {\mathrm{53}}^1\times {\mathrm{137}}^1\times {\mathrm{977}}^1$

素因数の和:1170

約数の個数: 16

約数和(自身を含む): 29152224

約数和(自身を除く): 7870233

約数列:

[1, 3, 53, 137, 159, 411, 977, 2931, 7261, 21783, 51781, 133849, 155343, 401547, 7093997, 21281991]

約数ペア:

[(1, 21281991), (3, 7093997), (53, 401547), (137, 155343), (159, 133849), (411, 51781), (977, 21783), (2931, 7261)]