20721813

素因数分解:

$3^1\times 7^1\times {\mathrm{37}}^1\times {\mathrm{26669}}^1$

素因数の和:26716

約数の個数: 16

約数和(自身を含む): 32430720

約数和(自身を除く): 11708907

約数列:

[1, 3, 7, 21, 37, 111, 259, 777, 26669, 80007, 186683, 560049, 986753, 2960259, 6907271, 20721813]

約数ペア:

[(1, 20721813), (3, 6907271), (7, 2960259), (21, 986753), (37, 560049), (111, 186683), (259, 80007), (777, 26669)]