21390668

素因数分解:

$2^2\times {\mathrm{13}}^2\times {\mathrm{31643}}^1$

素因数の和:31673

約数の個数: 18

約数和(自身を含む): 40535964

約数和(自身を除く): 19145296

約数列:

[1, 2, 4, 13, 26, 52, 169, 338, 676, 31643, 63286, 126572, 411359, 822718, 1645436, 5347667, 10695334, 21390668]

約数ペア:

[(1, 21390668), (2, 10695334), (4, 5347667), (13, 1645436), (26, 822718), (52, 411359), (169, 126572), (338, 63286), (676, 31643)]