81317840

素因数分解:

$2^4\times 5^1\times {\mathrm{509}}^1\times {\mathrm{1997}}^1$

素因数の和:2519

約数の個数: 40

約数和(自身を含む): 189530280

約数和(自身を除く): 108212440

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 509, 1018, 1997, 2036, 2545, 3994, 4072, 5090, 7988, 8144, 9985, 10180, 15976, 19970, 20360, 31952, 39940, 40720, 79880, 159760, 1016473, 2032946, 4065892, 5082365, 8131784, 10164730, 16263568, 20329460, 40658920, 81317840]

約数ペア:

[(1, 81317840), (2, 40658920), (4, 20329460), (5, 16263568), (8, 10164730), (10, 8131784), (16, 5082365), (20, 4065892), (40, 2032946), (80, 1016473), (509, 159760), (1018, 79880), (1997, 40720), (2036, 39940), (2545, 31952), (3994, 20360), (4072, 19970), (5090, 15976), (7988, 10180), (8144, 9985)]