20987.000000

素因数分解:

$2^5\times {\mathrm{41}}^1\times {\mathrm{487}}^1$

素因数の和:538

約数の個数: 24

約数和(自身を含む): 1291248

約数和(自身を除く): 652304

約数列:

[1, 2, 4, 8, 16, 32, 41, 82, 164, 328, 487, 656, 974, 1312, 1948, 3896, 7792, 15584, 19967, 39934, 79868, 159736, 319472, 638944]

約数ペア:

[(1, 638944), (2, 319472), (4, 159736), (8, 79868), (16, 39934), (32, 19967), (41, 15584), (82, 7792), (164, 3896), (328, 1948), (487, 1312), (656, 974)]