nine vs 9

nine and 9 both are nouns.

Word	Noun	Adjective	Verb	Adverb
nine	Yes	Yes	No	No
9	Yes	Yes	No	No

As adjectives, nine and 9 are synonyms defined as:

nine and 9: denoting a quantity consisting of one more than eight and one less than ten

Other synonyms of nine include ix.

As nouns, nine and 9 are synonyms defined as:

Other synonyms of nine include ennead, IX, Nina from Carolina, niner.

nine (noun)	9 (noun)
one of four playing cards in a deck with nine pips on the face	the cardinal number that is the sum of eight and one
a team of professional baseball players who play and travel together
the cardinal number that is the sum of eight and one

nine (adjective)	9 (adjective)
denoting a quantity consisting of one more than eight and one less than ten	denoting a quantity consisting of one more than eight and one less than ten