21991389

素因数分解:

$3^1\times 7^1\times {\mathrm{107}}^1\times {\mathrm{9787}}^1$

素因数の和:9904

約数の個数: 16

約数和(自身を含む): 33827328

約数和(自身を除く): 11835939

約数列:

[1, 3, 7, 21, 107, 321, 749, 2247, 9787, 29361, 68509, 205527, 1047209, 3141627, 7330463, 21991389]

約数ペア:

[(1, 21991389), (3, 7330463), (7, 3141627), (21, 1047209), (107, 205527), (321, 68509), (749, 29361), (2247, 9787)]