21006875

素因数分解:

$5^4\times {\mathrm{19}}^1\times {\mathrm{29}}^1\times {\mathrm{61}}^1$

素因数の和:129

約数の個数: 40

約数和(自身を含む): 29053200

約数和(自身を除く): 8046325

約数列:

[1, 5, 19, 25, 29, 61, 95, 125, 145, 305, 475, 551, 625, 725, 1159, 1525, 1769, 2375, 2755, 3625, 5795, 7625, 8845, 11875, 13775, 18125, 28975, 33611, 38125, 44225, 68875, 144875, 168055, 221125, 344375, 724375, 840275, 1105625, 4201375, 21006875]

約数ペア:

[(1, 21006875), (5, 4201375), (19, 1105625), (25, 840275), (29, 724375), (61, 344375), (95, 221125), (125, 168055), (145, 144875), (305, 68875), (475, 44225), (551, 38125), (625, 33611), (725, 28975), (1159, 18125), (1525, 13775), (1769, 11875), (2375, 8845), (2755, 7625), (3625, 5795)]