# Maxwell-Boltzmann distribution and total energy per unit volume

We know that

$$n(E) ~=~ \frac {2 \pi (N/V)}{(\pi k_B T)^{3/2}} E^{1/2} e^{-E/(k_B T)} dE,$$

where $V$ is total volume.

If then, how do we derive total energy per unit volume from this equation?