I just got a call from this number when I was sitting at my desk at work. My phone was on silent, so I missed the call and no message was left. After reading all of this I will not be answering if they call back.
I spoke with a representative at Wachovia (Arnold). This is indeed a Wachovia number. He said that it's a number used by their telemarketers within Wachovia. If you want to be removed from the call list, you must ask Wachovia to be removed from their call list....otherwise, they will keep calling.
Don't trust anyone saying this is a Wachovia phone number. If it is a "telemarketer" from within Wachovia they wouldn't ask stuff about your account, and if it were another company they wouldn't claim to be Wachovia. If you get these calls report it to Wachovia.