Your formula looks like it is set up as volume * density, which as jhb pointed out is the correct formula, but you have to make sure your units are correct. It sounds like either you interpreted a result of 57.7 g as 57.7 kg (i.e. 57,700 g), or possibly used the wrong units for volume. If you use cubic mm or cubic inches or something other than cubic cm for volume, then you’ll need to use a different number for density. What is the volume of your design?