You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[cyclopropyl(propan-2-ylcarbamoyl)amino]-N-propyl-1-oxa-9-azaspiro[5.5]undecane-9-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H36N4O3
assistant