You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-cyclopentyl-2-oxo-N-(5-pentan-2-yl-1H-pyrazol-3-yl)-3H-benzimidazole-5-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H27N5O2
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