21216978

素因数分解:

$2^1\times 3^4\times {\mathrm{130969}}^1$

素因数の和:130983

約数の個数: 20

約数和(自身を含む): 47542110

約数和(自身を除く): 26325132

約数列:

[1, 2, 3, 6, 9, 18, 27, 54, 81, 162, 130969, 261938, 392907, 785814, 1178721, 2357442, 3536163, 7072326, 10608489, 21216978]

約数ペア:

[(1, 21216978), (2, 10608489), (3, 7072326), (6, 3536163), (9, 2357442), (18, 1178721), (27, 785814), (54, 392907), (81, 261938), (162, 130969)]