20991505

素因数分解:

$5^1\times {\mathrm{29}}^1\times {\mathrm{71}}^1\times {\mathrm{2039}}^1$

素因数の和:2144

約数の個数: 16

約数和(自身を含む): 26438400

約数和(自身を除く): 5446895

約数列:

[1, 5, 29, 71, 145, 355, 2039, 2059, 10195, 10295, 59131, 144769, 295655, 723845, 4198301, 20991505]

約数ペア:

[(1, 20991505), (5, 4198301), (29, 723845), (71, 295655), (145, 144769), (355, 59131), (2039, 10295), (2059, 10195)]