20781520

素因数分解:

$2^4\times 5^1\times {\mathrm{47}}^1\times {\mathrm{5527}}^1$

素因数の和:5587

約数の個数: 40

約数和(自身を含む): 49353984

約数和(自身を除く): 28572464

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 47, 80, 94, 188, 235, 376, 470, 752, 940, 1880, 3760, 5527, 11054, 22108, 27635, 44216, 55270, 88432, 110540, 221080, 259769, 442160, 519538, 1039076, 1298845, 2078152, 2597690, 4156304, 5195380, 10390760, 20781520]

約数ペア:

[(1, 20781520), (2, 10390760), (4, 5195380), (5, 4156304), (8, 2597690), (10, 2078152), (16, 1298845), (20, 1039076), (40, 519538), (47, 442160), (80, 259769), (94, 221080), (188, 110540), (235, 88432), (376, 55270), (470, 44216), (752, 27635), (940, 22108), (1880, 11054), (3760, 5527)]