20991257

素因数分解:

$7^3\times {\mathrm{19}}^1\times {\mathrm{3221}}^1$

素因数の和:3261

約数の個数: 16

約数和(自身を含む): 25776000

約数和(自身を除く): 4784743

約数列:

[1, 7, 19, 49, 133, 343, 931, 3221, 6517, 22547, 61199, 157829, 428393, 1104803, 2998751, 20991257]

約数ペア:

[(1, 20991257), (7, 2998751), (19, 1104803), (49, 428393), (133, 157829), (343, 61199), (931, 22547), (3221, 6517)]