You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[2-[(3R,4R)-3-amino-4-fluoropiperidin-1-yl]-5,6-difluorobenzimidazol-1-yl]-N-(2-fluoroethyl)-N-methylacetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C17H21F4N5O
assistant