21681620

素因数分解:

$2^2\times 5^1\times {\mathrm{41}}^1\times {\mathrm{137}}^1\times {\mathrm{193}}^1$

素因数の和:380

約数の個数: 48

約数和(自身を含む): 47225808

約数和(自身を除く): 25544188

約数列:

[1, 2, 4, 5, 10, 20, 41, 82, 137, 164, 193, 205, 274, 386, 410, 548, 685, 772, 820, 965, 1370, 1930, 2740, 3860, 5617, 7913, 11234, 15826, 22468, 26441, 28085, 31652, 39565, 52882, 56170, 79130, 105764, 112340, 132205, 158260, 264410, 528820, 1084081, 2168162, 4336324, 5420405, 10840810, 21681620]

約数ペア:

[(1, 21681620), (2, 10840810), (4, 5420405), (5, 4336324), (10, 2168162), (20, 1084081), (41, 528820), (82, 264410), (137, 158260), (164, 132205), (193, 112340), (205, 105764), (274, 79130), (386, 56170), (410, 52882), (548, 39565), (685, 31652), (772, 28085), (820, 26441), (965, 22468), (1370, 15826), (1930, 11234), (2740, 7913), (3860, 5617)]