Number protons is what determines the element. 16 protons determines that the substance is sulphur.
The number of neutrons can vary according to the isotope. Â The mass number is the total count of neutrons and protons, so sulphur with a mass number of 34 has 34-16=18 neutrons.
32.065 is the weighted average of the atomic weights of different isotopes, so does not apply to a single isotope.