20521641

素因数分解:

$3^1\times 7^2\times {\mathrm{137}}^1\times {\mathrm{1019}}^1$

素因数の和:1173

約数の個数: 24

約数和(自身を含む): 32093280

約数和(自身を除く): 11571639

約数列:

[1, 3, 7, 21, 49, 137, 147, 411, 959, 1019, 2877, 3057, 6713, 7133, 20139, 21399, 49931, 139603, 149793, 418809, 977221, 2931663, 6840547, 20521641]

約数ペア:

[(1, 20521641), (3, 6840547), (7, 2931663), (21, 977221), (49, 418809), (137, 149793), (147, 139603), (411, 49931), (959, 21399), (1019, 20139), (2877, 7133), (3057, 6713)]