21038960

素因数分解:

$2^4\times 5^1\times {\mathrm{409}}^1\times {\mathrm{643}}^1$

素因数の和:1065

約数の個数: 40

約数和(自身を含む): 49111440

約数和(自身を除く): 28072480

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 409, 643, 818, 1286, 1636, 2045, 2572, 3215, 3272, 4090, 5144, 6430, 6544, 8180, 10288, 12860, 16360, 25720, 32720, 51440, 262987, 525974, 1051948, 1314935, 2103896, 2629870, 4207792, 5259740, 10519480, 21038960]

約数ペア:

[(1, 21038960), (2, 10519480), (4, 5259740), (5, 4207792), (8, 2629870), (10, 2103896), (16, 1314935), (20, 1051948), (40, 525974), (80, 262987), (409, 51440), (643, 32720), (818, 25720), (1286, 16360), (1636, 12860), (2045, 10288), (2572, 8180), (3215, 6544), (3272, 6430), (4090, 5144)]