19991990

素因数分解:

$2^1\times 5^1\times {\mathrm{19}}^1\times {\mathrm{43}}^1\times {\mathrm{2447}}^1$

素因数の和:2516

約数の個数: 32

約数和(自身を含む): 38776320

約数和(自身を除く): 18784330

約数列:

[1, 2, 5, 10, 19, 38, 43, 86, 95, 190, 215, 430, 817, 1634, 2447, 4085, 4894, 8170, 12235, 24470, 46493, 92986, 105221, 210442, 232465, 464930, 526105, 1052210, 1999199, 3998398, 9995995, 19991990]

約数ペア:

[(1, 19991990), (2, 9995995), (5, 3998398), (10, 1999199), (19, 1052210), (38, 526105), (43, 464930), (86, 232465), (95, 210442), (190, 105221), (215, 92986), (430, 46493), (817, 24470), (1634, 12235), (2447, 8170), (4085, 4894)]