You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (3S)-1-[1-[(1R)-1-(5-isocyanopyridin-2-yl)propyl]benzimidazol-2-yl]piperidin-3-amine by IUPAC nomenclature, provide its molecular formula.
user
C21H24N6
assistant