19901791

素因数分解:

$7^2\times {\mathrm{13}}^1\times {\mathrm{157}}^1\times {\mathrm{199}}^1$

素因数の和:383

約数の個数: 24

約数和(自身を含む): 25216800

約数和(自身を除く): 5315009

約数列:

[1, 7, 13, 49, 91, 157, 199, 637, 1099, 1393, 2041, 2587, 7693, 9751, 14287, 18109, 31243, 100009, 126763, 218701, 406159, 1530907, 2843113, 19901791]

約数ペア:

[(1, 19901791), (7, 2843113), (13, 1530907), (49, 406159), (91, 218701), (157, 126763), (199, 100009), (637, 31243), (1099, 18109), (1393, 14287), (2041, 9751), (2587, 7693)]