21990913

素因数分解:

$7^1\times {\mathrm{37}}^1\times {\mathrm{197}}^1\times {\mathrm{431}}^1$

素因数の和:672

約数の個数: 16

約数和(自身を含む): 26002944

約数和(自身を除く): 4012031

約数列:

[1, 7, 37, 197, 259, 431, 1379, 3017, 7289, 15947, 51023, 84907, 111629, 594349, 3141559, 21990913]

約数ペア:

[(1, 21990913), (7, 3141559), (37, 594349), (197, 111629), (259, 84907), (431, 51023), (1379, 15947), (3017, 7289)]