You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(2-bromophenyl)-1-[2-(2,4-dichlorophenyl)ethyl]-1-[1-(3-ethyl-4-oxoquinazolin-2-yl)propyl]urea is the IUPAC name of a molecule. Please give its molecular formula.
user
C28H27BrCl2N4O2
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