21207680

素因数分解:

$2^7\times 5^1\times {\mathrm{13}}^1\times {\mathrm{2549}}^1$

素因数の和:2581

約数の個数: 64

約数和(自身を含む): 54621000

約数和(自身を除く): 33413320

約数列:

[1, 2, 4, 5, 8, 10, 13, 16, 20, 26, 32, 40, 52, 64, 65, 80, 104, 128, 130, 160, 208, 260, 320, 416, 520, 640, 832, 1040, 1664, 2080, 2549, 4160, 5098, 8320, 10196, 12745, 20392, 25490, 33137, 40784, 50980, 66274, 81568, 101960, 132548, 163136, 165685, 203920, 265096, 326272, 331370, 407840, 530192, 662740, 815680, 1060384, 1325480, 1631360, 2120768, 2650960, 4241536, 5301920, 10603840, 21207680]

約数ペア:

[(1, 21207680), (2, 10603840), (4, 5301920), (5, 4241536), (8, 2650960), (10, 2120768), (13, 1631360), (16, 1325480), (20, 1060384), (26, 815680), (32, 662740), (40, 530192), (52, 407840), (64, 331370), (65, 326272), (80, 265096), (104, 203920), (128, 165685), (130, 163136), (160, 132548), (208, 101960), (260, 81568), (320, 66274), (416, 50980), (520, 40784), (640, 33137), (832, 25490), (1040, 20392), (1664, 12745), (2080, 10196), (2549, 8320), (4160, 5098)]