The telephone number is supplied by a company that supplies caller ID "decoy" phone numbers . See http://www.decoydigits.com/734-224-6194
This is the company's home page:
http://www.decoydigits.com/
Providing a spoofed caller ID telephone number is likely a legal business. The part that is not legal is using these spoofed caller ID numbers to hide a telemarketing scam. I say scam because hiding the real number alerts me to believe they are hiding something.
I've received three calls from a security systems sales company and another from a different business