necessarily vs of necessity

necessarily and of necessity both are adverbs.

Word	Noun	Adjective	Verb	Adverb
necessarily	No	No	No	Yes
of necessity	No	No	No	Yes

As adverbs, necessarily and of necessity are synonyms defined as:

necessarily and of necessity: in such a manner as could not be otherwise

Other synonyms of necessarily include inevitably, needs.

necessarily (adverb)	of necessity (adverb)
in an essential manner	in such a manner as could not be otherwise
as a highly likely consequence
in such a manner as could not be otherwise