CH
This is what i know..
If you dont know the number
dont answer. If it is important , they can always leave a voice mail or call you back
if they ask for your ssn or date of birth in the first 2 minutes of the conversation... Hung up
as long as you are not doing anything ilegal, you should be happy every day and be able to sleep at night.
Ps
nobody will give you free money - if it is too good to be true - it probably is not true