21720285

素因数分解:

$3^3\times 5^1\times {\mathrm{251}}^1\times {\mathrm{641}}^1$

素因数の和:906

約数の個数: 32

約数和(自身を含む): 38828160

約数和(自身を除く): 17107875

約数列:

[1, 3, 5, 9, 15, 27, 45, 135, 251, 641, 753, 1255, 1923, 2259, 3205, 3765, 5769, 6777, 9615, 11295, 17307, 28845, 33885, 86535, 160891, 482673, 804455, 1448019, 2413365, 4344057, 7240095, 21720285]

約数ペア:

[(1, 21720285), (3, 7240095), (5, 4344057), (9, 2413365), (15, 1448019), (27, 804455), (45, 482673), (135, 160891), (251, 86535), (641, 33885), (753, 28845), (1255, 17307), (1923, 11295), (2259, 9615), (3205, 6777), (3765, 5769)]