What is the atomic number of sodium chloride?

We can speak the the atomic number of its constituent elements, i.e. sodium, $Z = 11$, and chlorine, $Z = 17$, which numbers represent the number of PROTONS, fundamental, massive positively charged nuclear particles, but this is all we can say with respect to atomic number.
We could speak of the formula mass of sodium chloride, $58.44$ $g \cdot m o {l}^{-} 1$, but that's another definition.