There are 7,920,000 telephone numbers per area code and 335 area codes. See https://www.puc.texas.gov/industry/maps/areacodes/txareacodefaq.aspx https://www.puc

There are 7,920,000 telephone numbers per area code and 335 area codes. See https://www.puc.texas.gov/industry/maps/areacodes/txareacodefaq.aspx https://www.puc.texas.gov/industry/maps/areacodes/txareacode... and https://www.twilio.com/docs/glossary/north-american-area-codes https://www.twilio.com/docs/glossary/north-american-area-cod.... I don't know much about VOIP and how many of those numbers are allocated. So that over 2.5 billion total #s. Still I think you'd need extensions or something which probably would not work with texting, etc.