19988980

素因数分解:

$2^2\times 5^1\times {\mathrm{11}}^1\times {\mathrm{43}}^1\times {\mathrm{2113}}^1$

素因数の和:2176

約数の個数: 48

約数和(自身を含む): 46880064

約数和(自身を除く): 26891084

約数列:

[1, 2, 4, 5, 10, 11, 20, 22, 43, 44, 55, 86, 110, 172, 215, 220, 430, 473, 860, 946, 1892, 2113, 2365, 4226, 4730, 8452, 9460, 10565, 21130, 23243, 42260, 46486, 90859, 92972, 116215, 181718, 232430, 363436, 454295, 464860, 908590, 999449, 1817180, 1998898, 3997796, 4997245, 9994490, 19988980]

約数ペア:

[(1, 19988980), (2, 9994490), (4, 4997245), (5, 3997796), (10, 1998898), (11, 1817180), (20, 999449), (22, 908590), (43, 464860), (44, 454295), (55, 363436), (86, 232430), (110, 181718), (172, 116215), (215, 92972), (220, 90859), (430, 46486), (473, 42260), (860, 23243), (946, 21130), (1892, 10565), (2113, 9460), (2365, 8452), (4226, 4730)]