21978550

素因数分解:

$2^1\times 5^2\times {\mathrm{11}}^1\times {\mathrm{89}}^1\times {\mathrm{449}}^1$

素因数の和:561

約数の個数: 48

約数和(自身を含む): 45198000

約数和(自身を除く): 23219450

約数列:

[1, 2, 5, 10, 11, 22, 25, 50, 55, 89, 110, 178, 275, 445, 449, 550, 890, 898, 979, 1958, 2225, 2245, 4450, 4490, 4895, 4939, 9790, 9878, 11225, 22450, 24475, 24695, 39961, 48950, 49390, 79922, 123475, 199805, 246950, 399610, 439571, 879142, 999025, 1998050, 2197855, 4395710, 10989275, 21978550]

約数ペア:

[(1, 21978550), (2, 10989275), (5, 4395710), (10, 2197855), (11, 1998050), (22, 999025), (25, 879142), (50, 439571), (55, 399610), (89, 246950), (110, 199805), (178, 123475), (275, 79922), (445, 49390), (449, 48950), (550, 39961), (890, 24695), (898, 24475), (979, 22450), (1958, 11225), (2225, 9878), (2245, 9790), (4450, 4939), (4490, 4895)]