21991347

素因数分解:

$3^2\times 7^2\times {\mathrm{47}}^1\times {\mathrm{1061}}^1$

素因数の和:1128

約数の個数: 36

約数和(自身を含む): 37773216

約数和(自身を除く): 15781869

約数列:

[1, 3, 7, 9, 21, 47, 49, 63, 141, 147, 329, 423, 441, 987, 1061, 2303, 2961, 3183, 6909, 7427, 9549, 20727, 22281, 49867, 51989, 66843, 149601, 155967, 349069, 448803, 467901, 1047207, 2443483, 3141621, 7330449, 21991347]

約数ペア:

[(1, 21991347), (3, 7330449), (7, 3141621), (9, 2443483), (21, 1047207), (47, 467901), (49, 448803), (63, 349069), (141, 155967), (147, 149601), (329, 66843), (423, 51989), (441, 49867), (987, 22281), (1061, 20727), (2303, 9549), (2961, 7427), (3183, 6909)]