It’s said of a number (5)
I believe the answer is:
vocal
'it's said' is the definition.
(thesaurus)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for vocal that I've seen before include "Forthright in argument" , "not instrumental" , "With lots to say" , "Loud in complaining" , "Freely expressing opinions" .)