19996520

素因数分解:

$2^3\times 5^1\times {\mathrm{41}}^1\times {\mathrm{89}}^1\times {\mathrm{137}}^1$

素因数の和:278

約数の個数: 64

約数和(自身を含む): 46947600

約数和(自身を除く): 26951080

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 41, 82, 89, 137, 164, 178, 205, 274, 328, 356, 410, 445, 548, 685, 712, 820, 890, 1096, 1370, 1640, 1780, 2740, 3560, 3649, 5480, 5617, 7298, 11234, 12193, 14596, 18245, 22468, 24386, 28085, 29192, 36490, 44936, 48772, 56170, 60965, 72980, 97544, 112340, 121930, 145960, 224680, 243860, 487720, 499913, 999826, 1999652, 2499565, 3999304, 4999130, 9998260, 19996520]

約数ペア:

[(1, 19996520), (2, 9998260), (4, 4999130), (5, 3999304), (8, 2499565), (10, 1999652), (20, 999826), (40, 499913), (41, 487720), (82, 243860), (89, 224680), (137, 145960), (164, 121930), (178, 112340), (205, 97544), (274, 72980), (328, 60965), (356, 56170), (410, 48772), (445, 44936), (548, 36490), (685, 29192), (712, 28085), (820, 24386), (890, 22468), (1096, 18245), (1370, 14596), (1640, 12193), (1780, 11234), (2740, 7298), (3560, 5617), (3649, 5480)]