21780

素因数分解:

$2^2\times 3^2\times 5^1\times {\mathrm{11}}^2$

素因数の和:37

約数の個数: 54

約数和(自身を含む): 72618

約数和(自身を除く): 50838

約数列:

[1, 2, 3, 4, 5, 6, 9, 10, 11, 12, 15, 18, 20, 22, 30, 33, 36, 44, 45, 55, 60, 66, 90, 99, 110, 121, 132, 165, 180, 198, 220, 242, 330, 363, 396, 484, 495, 605, 660, 726, 990, 1089, 1210, 1452, 1815, 1980, 2178, 2420, 3630, 4356, 5445, 7260, 10890, 21780]

約数ペア:

[(1, 21780), (2, 10890), (3, 7260), (4, 5445), (5, 4356), (6, 3630), (9, 2420), (10, 2178), (11, 1980), (12, 1815), (15, 1452), (18, 1210), (20, 1089), (22, 990), (30, 726), (33, 660), (36, 605), (44, 495), (45, 484), (55, 396), (60, 363), (66, 330), (90, 242), (99, 220), (110, 198), (121, 180), (132, 165)]