21280005

素因数分解:

$3^2\times 5^1\times {\mathrm{17}}^1\times {\mathrm{27817}}^1$

素因数の和:27845

約数の個数: 24

約数和(自身を含む): 39056472

約数和(自身を除く): 17776467

約数列:

[1, 3, 5, 9, 15, 17, 45, 51, 85, 153, 255, 765, 27817, 83451, 139085, 250353, 417255, 472889, 1251765, 1418667, 2364445, 4256001, 7093335, 21280005]

約数ペア:

[(1, 21280005), (3, 7093335), (5, 4256001), (9, 2364445), (15, 1418667), (17, 1251765), (45, 472889), (51, 417255), (85, 250353), (153, 139085), (255, 83451), (765, 27817)]