19916991

素因数分解:

$3^2\times {\mathrm{71}}^2\times {\mathrm{439}}^1$

素因数の和:587

約数の個数: 18

約数和(自身を含む): 29246360

約数和(自身を除く): 9329369

約数列:

[1, 3, 9, 71, 213, 439, 639, 1317, 3951, 5041, 15123, 31169, 45369, 93507, 280521, 2212999, 6638997, 19916991]

約数ペア:

[(1, 19916991), (3, 6638997), (9, 2212999), (71, 280521), (213, 93507), (439, 45369), (639, 31169), (1317, 15123), (3951, 5041)]