Called and left about 45 seconds of dead air in a voicemail and then a prerecording says "Hello, This is United Healhcare, calling with important information about your healthcare benefits. Please call us back , toll-free, at 1-855-819-5917, between 8am and 5pm. Thank you."

Various other websites have shown this number to be from a woman who asks probing questions to try and get personal information such as social security numbers, birthdates, and home addresses. Don't give any of this info out.

Its a good idea never to give this info out unless you called the company and trust them already. No legitimate company will call you and then ask you for personal information to "verify it."