The electron volt is a unit of energy related to mass by the fundamental equation `E = m*c^2`.  Thus electron-volts, eV, are related to mass by  mass = energy/`c^2`

So, we have one atomic mass unit (u) = 9.31494061E08 `"eV"/c^2` and thus one `"eV"/c^2` = 1.073544150E-09 u

Notes

one atomic mass unit (u) = 9.31494061 E8 `"eV"/c^2`  = 1.660538921 E-27 kg

To see the `"eV"/c^2` units are appropriate, note that dividing Joules (a unit of energy like eV) by a velocity squared will give you units of mass:

`J =` `N * m` = `kg * m^2`/`s^2`

So, `J` / `(m/s)^2` = `((kg * m^2) / s^2)/(m/s)^2` = kg