21209020

素因数分解:

$2^2\times 5^1\times 7^1\times {\mathrm{197}}^1\times {\mathrm{769}}^1$

素因数の和:982

約数の個数: 48

約数和(自身を含む): 51226560

約数和(自身を除く): 30017540

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 70, 140, 197, 394, 769, 788, 985, 1379, 1538, 1970, 2758, 3076, 3845, 3940, 5383, 5516, 6895, 7690, 10766, 13790, 15380, 21532, 26915, 27580, 53830, 107660, 151493, 302986, 605972, 757465, 1060451, 1514930, 2120902, 3029860, 4241804, 5302255, 10604510, 21209020]

約数ペア:

[(1, 21209020), (2, 10604510), (4, 5302255), (5, 4241804), (7, 3029860), (10, 2120902), (14, 1514930), (20, 1060451), (28, 757465), (35, 605972), (70, 302986), (140, 151493), (197, 107660), (394, 53830), (769, 27580), (788, 26915), (985, 21532), (1379, 15380), (1538, 13790), (1970, 10766), (2758, 7690), (3076, 6895), (3845, 5516), (3940, 5383)]