20991075

素因数分解:

$3^1\times 5^2\times 7^1\times {\mathrm{39983}}^1$

素因数の和:40003

約数の個数: 24

約数和(自身を含む): 39664128

約数和(自身を除く): 18673053

約数列:

[1, 3, 5, 7, 15, 21, 25, 35, 75, 105, 175, 525, 39983, 119949, 199915, 279881, 599745, 839643, 999575, 1399405, 2998725, 4198215, 6997025, 20991075]

約数ペア:

[(1, 20991075), (3, 6997025), (5, 4198215), (7, 2998725), (15, 1399405), (21, 999575), (25, 839643), (35, 599745), (75, 279881), (105, 199915), (175, 119949), (525, 39983)]