840

素因数分解:

$2^3\times 3^1\times 5^1\times 7^1$

素因数の和:21

約数の個数: 32

約数和(自身を含む): 2880

約数和(自身を除く): 2040

約数列:

[1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 15, 20, 21, 24, 28, 30, 35, 40, 42, 56, 60, 70, 84, 105, 120, 140, 168, 210, 280, 420, 840]

約数ペア:

[(1, 840), (2, 420), (3, 280), (4, 210), (5, 168), (6, 140), (7, 120), (8, 105), (10, 84), (12, 70), (14, 60), (15, 56), (20, 42), (21, 40), (24, 35), (28, 30)]