One ring and a hangup

I receive calls from this number several times a week, always at different times. A message is never left; the caller hangs up as soon as my answering machine picks it up. All that shows on caller ID is Denver, CO.

Do not answer this number.  It's a scam.  Call only rings twice and never leaves a voicemail. Answering this call could give hackers access to your phone information.  Add this number to call reject list of block list on your phone.  Best practice would be to screen all calls that you don't recognize, if it's important, the person will leave a voicemail so you'll know it's legit.

This number left me a voice mail, it was selling "tax deductible life insurance".  Never heard that one before!

This automated call starts off by saying "This is not a sales call..."  Referred by a friend or neighbor in regards to some life insurance.