You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[(2-ethoxypyridin-4-yl)methyl]-3-[2-(4-fluoro-2-methylphenyl)ethyl]-2-methylguanidine;hydroiodide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H26FIN4O
assistant