Code Sample, a copy-pastable example if possible

import pandas as pd pd.to_numeric([-47393996303418497800, 'string'], errors='coerce')

Output:

array([-47393996303418497800, 'string'], dtype=object)

Problem description

to_numeric is silently not coercing 'string' to nan.

Seems similar to #17125 and #17007

pandas version 0.23.4