21720320

素因数分解:

$2^8\times 5^1\times {\mathrm{71}}^1\times {\mathrm{239}}^1$

素因数の和:331

約数の個数: 72

約数和(自身を含む): 52980480

約数和(自身を除く): 31260160

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 71, 80, 128, 142, 160, 239, 256, 284, 320, 355, 478, 568, 640, 710, 956, 1136, 1195, 1280, 1420, 1912, 2272, 2390, 2840, 3824, 4544, 4780, 5680, 7648, 9088, 9560, 11360, 15296, 16969, 18176, 19120, 22720, 30592, 33938, 38240, 45440, 61184, 67876, 76480, 84845, 90880, 135752, 152960, 169690, 271504, 305920, 339380, 543008, 678760, 1086016, 1357520, 2172032, 2715040, 4344064, 5430080, 10860160, 21720320]

約数ペア:

[(1, 21720320), (2, 10860160), (4, 5430080), (5, 4344064), (8, 2715040), (10, 2172032), (16, 1357520), (20, 1086016), (32, 678760), (40, 543008), (64, 339380), (71, 305920), (80, 271504), (128, 169690), (142, 152960), (160, 135752), (239, 90880), (256, 84845), (284, 76480), (320, 67876), (355, 61184), (478, 45440), (568, 38240), (640, 33938), (710, 30592), (956, 22720), (1136, 19120), (1195, 18176), (1280, 16969), (1420, 15296), (1912, 11360), (2272, 9560), (2390, 9088), (2840, 7648), (3824, 5680), (4544, 4780)]