21781521

素因数分解:

$3^3\times {\mathrm{43}}^1\times {\mathrm{73}}^1\times {\mathrm{257}}^1$

素因数の和:382

約数の個数: 32

約数和(自身を含む): 33601920

約数和(自身を除く): 11820399

約数列:

[1, 3, 9, 27, 43, 73, 129, 219, 257, 387, 657, 771, 1161, 1971, 2313, 3139, 6939, 9417, 11051, 18761, 28251, 33153, 56283, 84753, 99459, 168849, 298377, 506547, 806723, 2420169, 7260507, 21781521]

約数ペア:

[(1, 21781521), (3, 7260507), (9, 2420169), (27, 806723), (43, 506547), (73, 298377), (129, 168849), (219, 99459), (257, 84753), (387, 56283), (657, 33153), (771, 28251), (1161, 18761), (1971, 11051), (2313, 9417), (3139, 6939)]