21000851920

素因数分解:

$2^4\times 5^1\times {\mathrm{1291}}^1\times {\mathrm{203339}}^1$

素因数の和:204643

約数の個数: 40

約数和(自身を含む): 48865042080

約数和(自身を除く): 27864190160

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 1291, 2582, 5164, 6455, 10328, 12910, 20656, 25820, 51640, 103280, 203339, 406678, 813356, 1016695, 1626712, 2033390, 3253424, 4066780, 8133560, 16267120, 262510649, 525021298, 1050042596, 1312553245, 2100085192, 2625106490, 4200170384, 5250212980, 10500425960, 21000851920]

約数ペア:

[(1, 21000851920), (2, 10500425960), (4, 5250212980), (5, 4200170384), (8, 2625106490), (10, 2100085192), (16, 1312553245), (20, 1050042596), (40, 525021298), (80, 262510649), (1291, 16267120), (2582, 8133560), (5164, 4066780), (6455, 3253424), (10328, 2033390), (12910, 1626712), (20656, 1016695), (25820, 813356), (51640, 406678), (103280, 203339)]