21284740

素因数分解:

$2^2\times 5^1\times {\mathrm{41}}^1\times {\mathrm{101}}^1\times {\mathrm{257}}^1$

素因数の和:408

約数の個数: 48

約数和(自身を含む): 46421424

約数和(自身を除く): 25136684

約数列:

[1, 2, 4, 5, 10, 20, 41, 82, 101, 164, 202, 205, 257, 404, 410, 505, 514, 820, 1010, 1028, 1285, 2020, 2570, 4141, 5140, 8282, 10537, 16564, 20705, 21074, 25957, 41410, 42148, 51914, 52685, 82820, 103828, 105370, 129785, 210740, 259570, 519140, 1064237, 2128474, 4256948, 5321185, 10642370, 21284740]

約数ペア:

[(1, 21284740), (2, 10642370), (4, 5321185), (5, 4256948), (10, 2128474), (20, 1064237), (41, 519140), (82, 259570), (101, 210740), (164, 129785), (202, 105370), (205, 103828), (257, 82820), (404, 52685), (410, 51914), (505, 42148), (514, 41410), (820, 25957), (1010, 21074), (1028, 20705), (1285, 16564), (2020, 10537), (2570, 8282), (4141, 5140)]