21387905

素因数分解:

$5^1\times 7^1\times {\mathrm{11}}^1\times {\mathrm{73}}^1\times {\mathrm{761}}^1$

素因数の和:857

約数の個数: 32

約数和(自身を含む): 32479488

約数和(自身を除く): 11091583

約数列:

[1, 5, 7, 11, 35, 55, 73, 77, 365, 385, 511, 761, 803, 2555, 3805, 4015, 5327, 5621, 8371, 26635, 28105, 41855, 55553, 58597, 277765, 292985, 388871, 611083, 1944355, 3055415, 4277581, 21387905]

約数ペア:

[(1, 21387905), (5, 4277581), (7, 3055415), (11, 1944355), (35, 611083), (55, 388871), (73, 292985), (77, 277765), (365, 58597), (385, 55553), (511, 41855), (761, 28105), (803, 26635), (2555, 8371), (3805, 5621), (4015, 5327)]