20981560

素因数分解:

$2^3\times 5^1\times {\mathrm{61}}^1\times {\mathrm{8599}}^1$

素因数の和:8671

約数の個数: 32

約数和(自身を含む): 47988000

約数和(自身を除く): 27006440

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 61, 122, 244, 305, 488, 610, 1220, 2440, 8599, 17198, 34396, 42995, 68792, 85990, 171980, 343960, 524539, 1049078, 2098156, 2622695, 4196312, 5245390, 10490780, 20981560]

約数ペア:

[(1, 20981560), (2, 10490780), (4, 5245390), (5, 4196312), (8, 2622695), (10, 2098156), (20, 1049078), (40, 524539), (61, 343960), (122, 171980), (244, 85990), (305, 68792), (488, 42995), (610, 34396), (1220, 17198), (2440, 8599)]