IANAL, but according to the Reddit post mentioned in this thread, the number isn't yours:
"Consumer Google Voice is not a FCC-regulated Local Exchange Carrier, and you have no explicit nor implied rights to the indefinite use of Google Voice telephone numbers."
"If you want to port the number out of the suspended service, you can file a FCC Consumer Complaint, asking for the number to be unlocked for porting out. These complaints get reviewed by Google's legal department. FCC complaints will NOT get your Google Voice service restored, as there is no regulation requiring Google to offer free service."
https://old.reddit.com/r/Googlevoice/comments/17n4zl2/google...