You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 4-amino-N-(4-ethoxyphenyl)-2-(4-propan-2-ylpiperazin-1-yl)pyrimidine-5-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C20H28N6O2
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