20639120

素因数分解:

$2^4\times 5^1\times {\mathrm{257989}}^1$

素因数の和:258002

約数の個数: 20

約数和(自身を含む): 47986140

約数和(自身を除く): 27347020

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 257989, 515978, 1031956, 1289945, 2063912, 2579890, 4127824, 5159780, 10319560, 20639120]

約数ペア:

[(1, 20639120), (2, 10319560), (4, 5159780), (5, 4127824), (8, 2579890), (10, 2063912), (16, 1289945), (20, 1031956), (40, 515978), (80, 257989)]