How many gallons are in 32.4 liters?

Depends whether you mean US gallons or UK gallons, as they are different. 1 UK gallon = 4.5461 litres. 1 US gallon = 3.7854 litres. To find gallons from litres, divide your 43.49 by whichever of the two figures you need to use in order to make the correct conversion.