21052720

素因数分解:

$2^4\times 5^1\times {\mathrm{13}}^1\times {\mathrm{31}}^1\times {\mathrm{653}}^1$

素因数の和:710

約数の個数: 80

約数和(自身を含む): 54496512

約数和(自身を除く): 33443792

約数列:

[1, 2, 4, 5, 8, 10, 13, 16, 20, 26, 31, 40, 52, 62, 65, 80, 104, 124, 130, 155, 208, 248, 260, 310, 403, 496, 520, 620, 653, 806, 1040, 1240, 1306, 1612, 2015, 2480, 2612, 3224, 3265, 4030, 5224, 6448, 6530, 8060, 8489, 10448, 13060, 16120, 16978, 20243, 26120, 32240, 33956, 40486, 42445, 52240, 67912, 80972, 84890, 101215, 135824, 161944, 169780, 202430, 263159, 323888, 339560, 404860, 526318, 679120, 809720, 1052636, 1315795, 1619440, 2105272, 2631590, 4210544, 5263180, 10526360, 21052720]

約数ペア:

[(1, 21052720), (2, 10526360), (4, 5263180), (5, 4210544), (8, 2631590), (10, 2105272), (13, 1619440), (16, 1315795), (20, 1052636), (26, 809720), (31, 679120), (40, 526318), (52, 404860), (62, 339560), (65, 323888), (80, 263159), (104, 202430), (124, 169780), (130, 161944), (155, 135824), (208, 101215), (248, 84890), (260, 80972), (310, 67912), (403, 52240), (496, 42445), (520, 40486), (620, 33956), (653, 32240), (806, 26120), (1040, 20243), (1240, 16978), (1306, 16120), (1612, 13060), (2015, 10448), (2480, 8489), (2612, 8060), (3224, 6530), (3265, 6448), (4030, 5224)]