You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[1-(2,6-difluorophenyl)pyrrolidin-3-yl]-2-methyl-3-[(6-propan-2-yloxypyridin-3-yl)methyl]guanidine;hydroiodide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H28F2IN5O
assistant