$1$ $\mathrm{amu}$ (atomic mass unit) mass is equal to energy of

$1 amu=1.66\times {10}^{-27} \mathrm{kg}$

Equivalent energy can be calculated by using mass-energy equivalence equation
$E=m{c}^2$
$E=1.66\times {10}^{-27}\times {\left(3\times {10}^8\right)}^2 \mathrm{J}$

$1 \mathrm{MeV}={10}^6\times 1.6\times {10}^{-19} \mathrm{J}$ 

Using above equations we can get,

$E= 931 \mathrm{MeV}$