647780

素因数分解:

$2^2\times 5^1\times 7^2\times {\mathrm{661}}^1$

素因数の和:684

約数の個数: 36

約数和(自身を含む): 1584828

約数和(自身を除く): 937048

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 49, 70, 98, 140, 196, 245, 490, 661, 980, 1322, 2644, 3305, 4627, 6610, 9254, 13220, 18508, 23135, 32389, 46270, 64778, 92540, 129556, 161945, 323890, 647780]

約数ペア:

[(1, 647780), (2, 323890), (4, 161945), (5, 129556), (7, 92540), (10, 64778), (14, 46270), (20, 32389), (28, 23135), (35, 18508), (49, 13220), (70, 9254), (98, 6610), (140, 4627), (196, 3305), (245, 2644), (490, 1322), (661, 980)]