21505905

素因数分解:

$3^4\times 5^1\times {\mathrm{53101}}^1$

素因数の和:53118

約数の個数: 20

約数和(自身を含む): 38552052

約数和(自身を除く): 17046147

約数列:

[1, 3, 5, 9, 15, 27, 45, 81, 135, 405, 53101, 159303, 265505, 477909, 796515, 1433727, 2389545, 4301181, 7168635, 21505905]

約数ペア:

[(1, 21505905), (3, 7168635), (5, 4301181), (9, 2389545), (15, 1433727), (27, 796515), (45, 477909), (81, 265505), (135, 159303), (405, 53101)]