You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2,4-dichloro-N-[[1-(cyclopropylmethyl)-3-(propylsulfonylmethyl)cyclobutyl]methyl]benzamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H27Cl2NO3S
assistant