21387555

素因数分解:

$3^2\times 5^1\times 7^1\times {\mathrm{43}}^1\times {\mathrm{1579}}^1$

素因数の和:1640

約数の個数: 48

約数和(自身を含む): 43380480

約数和(自身を除く): 21992925

約数列:

[1, 3, 5, 7, 9, 15, 21, 35, 43, 45, 63, 105, 129, 215, 301, 315, 387, 645, 903, 1505, 1579, 1935, 2709, 4515, 4737, 7895, 11053, 13545, 14211, 23685, 33159, 55265, 67897, 71055, 99477, 165795, 203691, 339485, 475279, 497385, 611073, 1018455, 1425837, 2376395, 3055365, 4277511, 7129185, 21387555]

約数ペア:

[(1, 21387555), (3, 7129185), (5, 4277511), (7, 3055365), (9, 2376395), (15, 1425837), (21, 1018455), (35, 611073), (43, 497385), (45, 475279), (63, 339485), (105, 203691), (129, 165795), (215, 99477), (301, 71055), (315, 67897), (387, 55265), (645, 33159), (903, 23685), (1505, 14211), (1579, 13545), (1935, 11053), (2709, 7895), (4515, 4737)]