20981205

素因数分解:

$3^2\times 5^1\times 7^1\times {\mathrm{43}}^1\times {\mathrm{1549}}^1$

素因数の和:1610

約数の個数: 48

約数和(自身を含む): 42556800

約数和(自身を除く): 21575595

約数列:

[1, 3, 5, 7, 9, 15, 21, 35, 43, 45, 63, 105, 129, 215, 301, 315, 387, 645, 903, 1505, 1549, 1935, 2709, 4515, 4647, 7745, 10843, 13545, 13941, 23235, 32529, 54215, 66607, 69705, 97587, 162645, 199821, 333035, 466249, 487935, 599463, 999105, 1398747, 2331245, 2997315, 4196241, 6993735, 20981205]

約数ペア:

[(1, 20981205), (3, 6993735), (5, 4196241), (7, 2997315), (9, 2331245), (15, 1398747), (21, 999105), (35, 599463), (43, 487935), (45, 466249), (63, 333035), (105, 199821), (129, 162645), (215, 97587), (301, 69705), (315, 66607), (387, 54215), (645, 32529), (903, 23235), (1505, 13941), (1549, 13545), (1935, 10843), (2709, 7745), (4515, 4647)]