21071720

素因数分解:

$2^3\times 5^1\times {\mathrm{43}}^1\times {\mathrm{12251}}^1$

素因数の和:12305

約数の個数: 32

約数和(自身を含む): 48517920

約数和(自身を除く): 27446200

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 43, 86, 172, 215, 344, 430, 860, 1720, 12251, 24502, 49004, 61255, 98008, 122510, 245020, 490040, 526793, 1053586, 2107172, 2633965, 4214344, 5267930, 10535860, 21071720]

約数ペア:

[(1, 21071720), (2, 10535860), (4, 5267930), (5, 4214344), (8, 2633965), (10, 2107172), (20, 1053586), (40, 526793), (43, 490040), (86, 245020), (172, 122510), (215, 98008), (344, 61255), (430, 49004), (860, 24502), (1720, 12251)]