francium vs atomic number 87

francium and atomic number 87 both are nouns.

Word	Noun	Adjective	Verb	Adverb
francium	Yes	No	No	No
atomic number 87	Yes	No	No	No

As nouns, francium and atomic number 87 are synonyms defined as:

francium and atomic number 87: a radioactive element of the alkali-metal group discovered as a disintegration product of actinium

Other synonyms of francium include Fr.

francium (noun)	atomic number 87 (noun)
a radioactive element of the alkali-metal group discovered as a disintegration product of actinium	a radioactive element of the alkali-metal group discovered as a disintegration product of actinium