19900000

素因数分解:

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

素因数の和:234

約数の個数: 72

約数和(自身を含む): 49215600

約数和(自身を除く): 29315600

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 25, 32, 40, 50, 80, 100, 125, 160, 199, 200, 250, 398, 400, 500, 625, 796, 800, 995, 1000, 1250, 1592, 1990, 2000, 2500, 3125, 3184, 3980, 4000, 4975, 5000, 6250, 6368, 7960, 9950, 10000, 12500, 15920, 19900, 20000, 24875, 25000, 31840, 39800, 49750, 50000, 79600, 99500, 100000, 124375, 159200, 199000, 248750, 398000, 497500, 621875, 796000, 995000, 1243750, 1990000, 2487500, 3980000, 4975000, 9950000, 19900000]

約数ペア:

[(1, 19900000), (2, 9950000), (4, 4975000), (5, 3980000), (8, 2487500), (10, 1990000), (16, 1243750), (20, 995000), (25, 796000), (32, 621875), (40, 497500), (50, 398000), (80, 248750), (100, 199000), (125, 159200), (160, 124375), (199, 100000), (200, 99500), (250, 79600), (398, 50000), (400, 49750), (500, 39800), (625, 31840), (796, 25000), (800, 24875), (995, 20000), (1000, 19900), (1250, 15920), (1592, 12500), (1990, 10000), (2000, 9950), (2500, 7960), (3125, 6368), (3184, 6250), (3980, 5000), (4000, 4975)]