Question

In order to be neutral, an atom has to contain equal numbers of _______

Answer 1

In order to be electrically neutral, an atom has to contain
equal numbers of protons (with their positive charges) and
electrons (with their negative charges).

Answer 2

For an atom to be neutral protons and electrons have to be same. 
They have to have the same number of protons and electrons. 
The negative and positive charge have to be equal.  

If the negative and positive charges are not equal the atom is not neutral