20997921

素因数分解:

$3^1\times 7^2\times {\mathrm{83}}^1\times {\mathrm{1721}}^1$

素因数の和:1821

約数の個数: 24

約数和(自身を含む): 32979744

約数和(自身を除く): 11981823

約数列:

[1, 3, 7, 21, 49, 83, 147, 249, 581, 1721, 1743, 4067, 5163, 12047, 12201, 36141, 84329, 142843, 252987, 428529, 999901, 2999703, 6999307, 20997921]

約数ペア:

[(1, 20997921), (3, 6999307), (7, 2999703), (21, 999901), (49, 428529), (83, 252987), (147, 142843), (249, 84329), (581, 36141), (1721, 12201), (1743, 12047), (4067, 5163)]