21990440

素因数分解:

$2^3\times 5^1\times {\mathrm{79}}^1\times {\mathrm{6959}}^1$

素因数の和:7049

約数の個数: 32

約数和(自身を含む): 50112000

約数和(自身を除く): 28121560

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 79, 158, 316, 395, 632, 790, 1580, 3160, 6959, 13918, 27836, 34795, 55672, 69590, 139180, 278360, 549761, 1099522, 2199044, 2748805, 4398088, 5497610, 10995220, 21990440]

約数ペア:

[(1, 21990440), (2, 10995220), (4, 5497610), (5, 4398088), (8, 2748805), (10, 2199044), (20, 1099522), (40, 549761), (79, 278360), (158, 139180), (316, 69590), (395, 55672), (632, 34795), (790, 27836), (1580, 13918), (3160, 6959)]