21398890

素因数分解:

$2^1\times 5^1\times {\mathrm{389}}^1\times {\mathrm{5501}}^1$

素因数の和:5897

約数の個数: 16

約数和(自身を含む): 38624040

約数和(自身を除く): 17225150

約数列:

[1, 2, 5, 10, 389, 778, 1945, 3890, 5501, 11002, 27505, 55010, 2139889, 4279778, 10699445, 21398890]

約数ペア:

[(1, 21398890), (2, 10699445), (5, 4279778), (10, 2139889), (389, 55010), (778, 27505), (1945, 11002), (3890, 5501)]