unsuccessful vs success

unsuccessful is not a noun while success is a noun.

Word	Noun	Adjective	Verb	Adverb
unsuccessful	No	Yes	No	No
success	Yes	No	No	No

unsuccessful (noun)	success (noun)
	an attainment that is successful
	an event that accomplishes its intended purpose
	a person with a record of successes
	a state of prosperity or fame

unsuccessful (adjective)	success (adjective)
not successful; having failed or having an unfavorable outcome
failing to accomplish an intended result