19780720

素因数分解:

$2^4\times 5^1\times {\mathrm{247259}}^1$

素因数の和:247272

約数の個数: 20

約数和(自身を含む): 45990360

約数和(自身を除く): 26209640

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 247259, 494518, 989036, 1236295, 1978072, 2472590, 3956144, 4945180, 9890360, 19780720]

約数ペア:

[(1, 19780720), (2, 9890360), (4, 4945180), (5, 3956144), (8, 2472590), (10, 1978072), (16, 1236295), (20, 989036), (40, 494518), (80, 247259)]