20811987

素因数分解:

$3^2\times 7^1\times {\mathrm{23}}^1\times {\mathrm{53}}^1\times {\mathrm{271}}^1$

素因数の和:360

約数の個数: 48

約数和(自身を含む): 36661248

約数和(自身を除く): 15849261

約数列:

[1, 3, 7, 9, 21, 23, 53, 63, 69, 159, 161, 207, 271, 371, 477, 483, 813, 1113, 1219, 1449, 1897, 2439, 3339, 3657, 5691, 6233, 8533, 10971, 14363, 17073, 18699, 25599, 43089, 43631, 56097, 76797, 100541, 129267, 130893, 301623, 330349, 392679, 904869, 991047, 2312443, 2973141, 6937329, 20811987]

約数ペア:

[(1, 20811987), (3, 6937329), (7, 2973141), (9, 2312443), (21, 991047), (23, 904869), (53, 392679), (63, 330349), (69, 301623), (159, 130893), (161, 129267), (207, 100541), (271, 76797), (371, 56097), (477, 43631), (483, 43089), (813, 25599), (1113, 18699), (1219, 17073), (1449, 14363), (1897, 10971), (2439, 8533), (3339, 6233), (3657, 5691)]