20991490

素因数分解:

$2^1\times 5^1\times {\mathrm{13}}^2\times {\mathrm{12421}}^1$

素因数の和:12454

約数の個数: 24

約数和(自身を含む): 40918068

約数和(自身を除く): 19926578

約数列:

[1, 2, 5, 10, 13, 26, 65, 130, 169, 338, 845, 1690, 12421, 24842, 62105, 124210, 161473, 322946, 807365, 1614730, 2099149, 4198298, 10495745, 20991490]

約数ペア:

[(1, 20991490), (2, 10495745), (5, 4198298), (10, 2099149), (13, 1614730), (26, 807365), (65, 322946), (130, 161473), (169, 124210), (338, 62105), (845, 24842), (1690, 12421)]