You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 6-[3-[4-[2,6-di(phenanthren-9-yl)pyrimidin-4-yl]phenyl]phenyl]benzo[k]phenanthridine by IUPAC nomenclature, provide its molecular formula.
user
C61H37N3
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