You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[4-fluoro-2-(4,4,4-trifluorobutoxy)phenyl]-N-[3-(methylsulfonylmethyl)phenyl]-1,3,5-triazin-2-amine is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H20F4N4O3S
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