20181820

素因数分解:

$2^2\times 5^1\times {\mathrm{97}}^1\times {\mathrm{101}}^1\times {\mathrm{103}}^1$

素因数の和:310

約数の個数: 48

約数和(自身を含む): 43662528

約数和(自身を除く): 23480708

約数列:

[1, 2, 4, 5, 10, 20, 97, 101, 103, 194, 202, 206, 388, 404, 412, 485, 505, 515, 970, 1010, 1030, 1940, 2020, 2060, 9797, 9991, 10403, 19594, 19982, 20806, 39188, 39964, 41612, 48985, 49955, 52015, 97970, 99910, 104030, 195940, 199820, 208060, 1009091, 2018182, 4036364, 5045455, 10090910, 20181820]

約数ペア:

[(1, 20181820), (2, 10090910), (4, 5045455), (5, 4036364), (10, 2018182), (20, 1009091), (97, 208060), (101, 199820), (103, 195940), (194, 104030), (202, 99910), (206, 97970), (388, 52015), (404, 49955), (412, 48985), (485, 41612), (505, 39964), (515, 39188), (970, 20806), (1010, 19982), (1030, 19594), (1940, 10403), (2020, 9991), (2060, 9797)]