21257180

素因数分解:

$2^2\times 5^1\times 7^2\times {\mathrm{109}}^1\times {\mathrm{199}}^1$

素因数の和:331

約数の個数: 72

約数和(自身を含む): 52668000

約数和(自身を除く): 31410820

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 49, 70, 98, 109, 140, 196, 199, 218, 245, 398, 436, 490, 545, 763, 796, 980, 995, 1090, 1393, 1526, 1990, 2180, 2786, 3052, 3815, 3980, 5341, 5572, 6965, 7630, 9751, 10682, 13930, 15260, 19502, 21364, 21691, 26705, 27860, 39004, 43382, 48755, 53410, 86764, 97510, 106820, 108455, 151837, 195020, 216910, 303674, 433820, 607348, 759185, 1062859, 1518370, 2125718, 3036740, 4251436, 5314295, 10628590, 21257180]

約数ペア:

[(1, 21257180), (2, 10628590), (4, 5314295), (5, 4251436), (7, 3036740), (10, 2125718), (14, 1518370), (20, 1062859), (28, 759185), (35, 607348), (49, 433820), (70, 303674), (98, 216910), (109, 195020), (140, 151837), (196, 108455), (199, 106820), (218, 97510), (245, 86764), (398, 53410), (436, 48755), (490, 43382), (545, 39004), (763, 27860), (796, 26705), (980, 21691), (995, 21364), (1090, 19502), (1393, 15260), (1526, 13930), (1990, 10682), (2180, 9751), (2786, 7630), (3052, 6965), (3815, 5572), (3980, 5341)]