Avogadro's number vs Avogadro number

Avogadro's number and Avogadro number both are nouns.

Word	Noun	Adjective	Verb	Adverb
Avogadro's number	Yes	No	No	No
Avogadro number	Yes	No	No	No

As nouns, Avogadro's number and Avogadro number are synonyms defined as:

Avogadro's number and Avogadro number: the number of molecules in a mole of a substance (approximately 602,250,000,000,000,000,000,000)

Avogadro's number (noun)	Avogadro number (noun)
the number of molecules in a mole of a substance (approximately 602,250,000,000,000,000,000,000)	the number of molecules in a mole of a substance (approximately 602,250,000,000,000,000,000,000)