21257395

素因数分解:

$5^1\times {\mathrm{17}}^2\times {\mathrm{47}}^1\times {\mathrm{313}}^1$

素因数の和:399

約数の個数: 24

約数和(自身を含む): 27762624

約数和(自身を除く): 6505229

約数列:

[1, 5, 17, 47, 85, 235, 289, 313, 799, 1445, 1565, 3995, 5321, 13583, 14711, 26605, 67915, 73555, 90457, 250087, 452285, 1250435, 4251479, 21257395]

約数ペア:

[(1, 21257395), (5, 4251479), (17, 1250435), (47, 452285), (85, 250087), (235, 90457), (289, 73555), (313, 67915), (799, 26605), (1445, 14711), (1565, 13583), (3995, 5321)]