217821121

素因数分解:

$7^4\times {\mathrm{257}}^1\times {\mathrm{353}}^1$

素因数の和:638

約数の個数: 20

約数和(自身を含む): 255820932

約数和(自身を除く): 37999811

約数列:

[1, 7, 49, 257, 343, 353, 1799, 2401, 2471, 12593, 17297, 88151, 90721, 121079, 617057, 635047, 847553, 4445329, 31117303, 217821121]

約数ペア:

[(1, 217821121), (7, 31117303), (49, 4445329), (257, 847553), (343, 635047), (353, 617057), (1799, 121079), (2401, 90721), (2471, 88151), (12593, 17297)]