You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[4-chloro-2-[5-[3-[(2-chlorophenyl)methyl]-2-iminobenzimidazol-1-yl]pyridin-2-yl]phenyl]acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C27H21Cl2N5O
assistant