21279920

素因数分解:

$2^4\times 5^1\times {\mathrm{17}}^1\times {\mathrm{15647}}^1$

素因数の和:15677

約数の個数: 40

約数和(自身を含む): 52389504

約数和(自身を除く): 31109584

約数列:

[1, 2, 4, 5, 8, 10, 16, 17, 20, 34, 40, 68, 80, 85, 136, 170, 272, 340, 680, 1360, 15647, 31294, 62588, 78235, 125176, 156470, 250352, 265999, 312940, 531998, 625880, 1063996, 1251760, 1329995, 2127992, 2659990, 4255984, 5319980, 10639960, 21279920]

約数ペア:

[(1, 21279920), (2, 10639960), (4, 5319980), (5, 4255984), (8, 2659990), (10, 2127992), (16, 1329995), (17, 1251760), (20, 1063996), (34, 625880), (40, 531998), (68, 312940), (80, 265999), (85, 250352), (136, 156470), (170, 125176), (272, 78235), (340, 62588), (680, 31294), (1360, 15647)]