numeral vs numerical

numeral is a noun but numerical is not a noun.

Word	Noun	Adjective	Verb	Adverb
numeral	Yes	Yes	No	No
numerical	No	Yes	No	No

As adjectives, numeral and numerical are synonyms defined as:

Other synonyms of numeral include numeric.

numeral (noun)	numerical (noun)
a symbol used to represent a number
a word expressing a number.

numeral (adjective)	numerical (adjective)
of or relating to or denoting numbers	relating to or having ability to think in or work with numbers
	of or relating to or denoting numbers
	measured or expressed in numbers