Does each bitcoin have a unique identifier, regardless who owns it? Does each satoshi have a unique identifier?
Satoshi is a unit of bitcoin and it means if you have satoshis, you have bitcoins.[Did you know?] Bitcoin Table of Units
Not your keys, not your coins. Keys here are private keys, not public keys. Bitcoin private keys are unique and only you own it when you create your Bitcoin wallet with a non custodial wallet software and if you do it offline.
If you believe in math.
