Benjamin Harrison, born in North Bend, 3 mi away, is the closest. Next door, Cincinnati lists 31, led by Steven Spielberg. So far, no famous person on record was born in Mack. 705 of the towns in Ohio list at least one person.
#1 best knownBenjamin HarrisonPolitics & Law · 1833–1901+10more
From Wikidata and Wikipedia: people whose birthplace is Mack and whose English Wikipedia article agrees, ranked by how many Wikipedia languages cover each person. Nearby people are those born in a town within 35 miles; distances are town center to town center. People known mainly for crimes, and adult performers, aren’t listed. “The usual town” = everyone born in the towns gathered so far.