21257860

素因数分解:

$2^2\times 5^1\times {\mathrm{13}}^1\times {\mathrm{81761}}^1$

素因数の和:81783

約数の個数: 24

約数和(自身を含む): 48076056

約数和(自身を除く): 26818196

約数列:

[1, 2, 4, 5, 10, 13, 20, 26, 52, 65, 130, 260, 81761, 163522, 327044, 408805, 817610, 1062893, 1635220, 2125786, 4251572, 5314465, 10628930, 21257860]

約数ペア:

[(1, 21257860), (2, 10628930), (4, 5314465), (5, 4251572), (10, 2125786), (13, 1635220), (20, 1062893), (26, 817610), (52, 408805), (65, 327044), (130, 163522), (260, 81761)]