You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-[[N-ethyl-N'-[(1-phenylsulfanylcyclopropyl)methyl]carbamimidoyl]amino]ethyl]-2-methylpropanamide;hydroiodide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H31IN4OS
assistant