21278020

素因数分解:

$2^2\times 5^1\times {\mathrm{61}}^1\times {\mathrm{107}}^1\times {\mathrm{163}}^1$

素因数の和:340

約数の個数: 48

約数和(自身を含む): 46122048

約数和(自身を除く): 24844028

約数列:

[1, 2, 4, 5, 10, 20, 61, 107, 122, 163, 214, 244, 305, 326, 428, 535, 610, 652, 815, 1070, 1220, 1630, 2140, 3260, 6527, 9943, 13054, 17441, 19886, 26108, 32635, 34882, 39772, 49715, 65270, 69764, 87205, 99430, 130540, 174410, 198860, 348820, 1063901, 2127802, 4255604, 5319505, 10639010, 21278020]

約数ペア:

[(1, 21278020), (2, 10639010), (4, 5319505), (5, 4255604), (10, 2127802), (20, 1063901), (61, 348820), (107, 198860), (122, 174410), (163, 130540), (214, 99430), (244, 87205), (305, 69764), (326, 65270), (428, 49715), (535, 39772), (610, 34882), (652, 32635), (815, 26108), (1070, 19886), (1220, 17441), (1630, 13054), (2140, 9943), (3260, 6527)]