20721555

素因数分解:

$3^3\times 5^1\times {\mathrm{17}}^1\times {\mathrm{9029}}^1$

素因数の和:9060

約数の個数: 32

約数和(自身を含む): 39009600

約数和(自身を除く): 18288045

約数列:

[1, 3, 5, 9, 15, 17, 27, 45, 51, 85, 135, 153, 255, 459, 765, 2295, 9029, 27087, 45145, 81261, 135435, 153493, 243783, 406305, 460479, 767465, 1218915, 1381437, 2302395, 4144311, 6907185, 20721555]

約数ペア:

[(1, 20721555), (3, 6907185), (5, 4144311), (9, 2302395), (15, 1381437), (17, 1218915), (27, 767465), (45, 460479), (51, 406305), (85, 243783), (135, 153493), (153, 135435), (255, 81261), (459, 45145), (765, 27087), (2295, 9029)]