Who called from 2400000000

Received call from 240-000-0000.  When a male voice tried to sell me I explained I did not want his product (based on the phone number).  He rudely asked me (in a thick accent) if I even knew what a credit card was.  I explained yes, I did, and he didn't need to be rude.  He followed with a "[***] off" phrase.  Unprofessional, unnecessary.

Just received this call on my cell, left no answer. I appreciate the info provided by other posters to this site.

Baltimore cell. did not answer

call from Maryland. did not answer, no message.

( 240) 000-0000 is calling my cellphone and I want them to stop.