How does the nucleus of a copper atom compare to the nucleus of a nickel atom?

$N i , Z = 28$ contains ONE LESS PROTON, one less positively charge massive nuclear particle, than $C u , Z = 29$.
This difference in the $Z$ enables us to identify the different elements as copper and nickel respectively. The nuclei contain 30 or so neutrons, but these differentiate the $\text{isotopes}$ of each element, the number of neutrons do not differentiate the $\text{identity}$ of each element.