cardinal vs twenty-one

cardinal and twenty-one both are nouns.

Word	Noun	Adjective	Verb	Adverb
cardinal	Yes	Yes	No	No
twenty-one	Yes	Yes	No	No

cardinal (noun)	twenty-one (noun)
crested thick-billed North American finch having bright red plumage in the male	a gambling game using cards; the object is to hold cards having a higher count than those dealt to the banker up to but not exceeding 21
a variable color averaging a vivid red	the cardinal number that is the sum of twenty and one
(Roman Catholic Church) one of a group of more than 100 prominent bishops in the Sacred College who advise the Pope and elect new Popes
the number of elements in a mathematical set; denotes a quantity but not the order

cardinal (adjective)	twenty-one (adjective)
being or denoting a numerical quantity but not order	being one more than twenty
serving as an essential component