five-hitter vs 5-hitter

five-hitter and 5-hitter both are nouns.

Word	Noun	Adjective	Verb	Adverb
five-hitter	Yes	No	No	No
5-hitter	Yes	No	No	No

As nouns, five-hitter and 5-hitter are synonyms defined as:

five-hitter and 5-hitter: a game in which a pitcher allows the opposing team 5 hits

five-hitter (noun)	5-hitter (noun)
a game in which a pitcher allows the opposing team 5 hits	a game in which a pitcher allows the opposing team 5 hits