21571809

素因数分解:

$3^1\times 7^2\times {\mathrm{257}}^1\times {\mathrm{571}}^1$

素因数の和:845

約数の個数: 24

約数和(自身を含む): 33647328

約数和(自身を除く): 12075519

約数列:

[1, 3, 7, 21, 49, 147, 257, 571, 771, 1713, 1799, 3997, 5397, 11991, 12593, 27979, 37779, 83937, 146747, 440241, 1027229, 3081687, 7190603, 21571809]

約数ペア:

[(1, 21571809), (3, 7190603), (7, 3081687), (21, 1027229), (49, 440241), (147, 146747), (257, 83937), (571, 37779), (771, 27979), (1713, 12593), (1799, 11991), (3997, 5397)]