640780

素因数分解:

$2^2\times 5^1\times 7^1\times {\mathrm{23}}^1\times {\mathrm{199}}^1$

素因数の和:238

約数の個数: 48

約数和(自身を含む): 1612800

約数和(自身を除く): 972020

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 23, 28, 35, 46, 70, 92, 115, 140, 161, 199, 230, 322, 398, 460, 644, 796, 805, 995, 1393, 1610, 1990, 2786, 3220, 3980, 4577, 5572, 6965, 9154, 13930, 18308, 22885, 27860, 32039, 45770, 64078, 91540, 128156, 160195, 320390, 640780]

約数ペア:

[(1, 640780), (2, 320390), (4, 160195), (5, 128156), (7, 91540), (10, 64078), (14, 45770), (20, 32039), (23, 27860), (28, 22885), (35, 18308), (46, 13930), (70, 9154), (92, 6965), (115, 5572), (140, 4577), (161, 3980), (199, 3220), (230, 2786), (322, 1990), (398, 1610), (460, 1393), (644, 995), (796, 805)]