A swimming pool, in the shape of a rectangular prism, is 50 meters long, 25 meters wide, and 3 meters deep. A liter is the same as 0.001 cubic meters. How many liters of water are needed to completely fill the pool?

I understand half of this question. You have to find the volume of the swimming pool by using B x W x H, which is 50 x 25 x 3 = 3,750 meters. What I don't understand is how to covert 750 meters into liters. Help...?