21154040

素因数分解:

$2^3\times 5^1\times {\mathrm{509}}^1\times {\mathrm{1039}}^1$

素因数の和:1559

約数の個数: 32

約数和(自身を含む): 47736000

約数和(自身を除く): 26581960

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 509, 1018, 1039, 2036, 2078, 2545, 4072, 4156, 5090, 5195, 8312, 10180, 10390, 20360, 20780, 41560, 528851, 1057702, 2115404, 2644255, 4230808, 5288510, 10577020, 21154040]

約数ペア:

[(1, 21154040), (2, 10577020), (4, 5288510), (5, 4230808), (8, 2644255), (10, 2115404), (20, 1057702), (40, 528851), (509, 41560), (1018, 20780), (1039, 20360), (2036, 10390), (2078, 10180), (2545, 8312), (4072, 5195), (4156, 5090)]