19991180

素因数分解:

$2^2\times 5^1\times {\mathrm{11}}^1\times {\mathrm{89}}^1\times {\mathrm{1021}}^1$

素因数の和:1130

約数の個数: 48

約数和(自身を含む): 46357920

約数和(自身を除く): 26366740

約数列:

[1, 2, 4, 5, 10, 11, 20, 22, 44, 55, 89, 110, 178, 220, 356, 445, 890, 979, 1021, 1780, 1958, 2042, 3916, 4084, 4895, 5105, 9790, 10210, 11231, 19580, 20420, 22462, 44924, 56155, 90869, 112310, 181738, 224620, 363476, 454345, 908690, 999559, 1817380, 1999118, 3998236, 4997795, 9995590, 19991180]

約数ペア:

[(1, 19991180), (2, 9995590), (4, 4997795), (5, 3998236), (10, 1999118), (11, 1817380), (20, 999559), (22, 908690), (44, 454345), (55, 363476), (89, 224620), (110, 181738), (178, 112310), (220, 90869), (356, 56155), (445, 44924), (890, 22462), (979, 20420), (1021, 19580), (1780, 11231), (1958, 10210), (2042, 9790), (3916, 5105), (4084, 4895)]