You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1,3-dioxo-2-azaspiro[4.5]decan-2-yl)methyl-methyl-[[4-(methylcarbamoyl)phenyl]methyl]azanium The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H28N3O3+
assistant