20991009

素因数分解:

$3^1\times {\mathrm{13}}^1\times {\mathrm{43}}^1\times {\mathrm{12517}}^1$

素因数の和:12576

約数の個数: 16

約数和(自身を含む): 30844352

約数和(自身を除く): 9853343

約数列:

[1, 3, 13, 39, 43, 129, 559, 1677, 12517, 37551, 162721, 488163, 538231, 1614693, 6997003, 20991009]

約数ペア:

[(1, 20991009), (3, 6997003), (13, 1614693), (39, 538231), (43, 488163), (129, 162721), (559, 37551), (1677, 12517)]