21420765

素因数分解:

$3^2\times 5^1\times {\mathrm{17}}^1\times {\mathrm{28001}}^1$

素因数の和:28029

約数の個数: 24

約数和(自身を含む): 39314808

約数和(自身を除く): 17894043

約数列:

[1, 3, 5, 9, 15, 17, 45, 51, 85, 153, 255, 765, 28001, 84003, 140005, 252009, 420015, 476017, 1260045, 1428051, 2380085, 4284153, 7140255, 21420765]

約数ペア:

[(1, 21420765), (3, 7140255), (5, 4284153), (9, 2380085), (15, 1428051), (17, 1260045), (45, 476017), (51, 420015), (85, 252009), (153, 140005), (255, 84003), (765, 28001)]