Didn't answer when I saw the number.  I too noticed though that it had too many numbers.  506 is the international country code from Costa Rica.  I don't know if this is where the call came from (this is also the area code for New Brunswick, Canada).  I'm sure whatever they are trying to sell is a scam.

Pre-recorded drivel about my supposed "last chance to reduce my credit card interest rates"...  These assclowns have been calling about 1-2x per week for months...  They refuse to put anyone on their internal do not call list, and do not comply with the National Do Not Call List either.  In fact, when you ask them to remove you - they hang up!

Didn't tell the company name until I asked, then told me "Account Services".

"I've never heard of you guys, where are you based?"
*click*

This is a scam!  They're just looking to steal your credit card info - do not give any info out.  If you ask to be removed from the call list they just hang up or cuss at you and keep calling back.  I am on the Do Not Call list, but it appears they could care less.  They're either re-routing through an international line or spoofing the number so it cannot be traced and the telemarketers cannot be prosecuted.  Phone company can't do anything or block number because it is an 11 digit number.

I've told them I'm on the do not call list and asked them to take me off their list several times now. They keep calling me. Wish I knew who they were so I could pursue further action.