I got a missed call from this unfamiliar area code and I called them back just to hear that the number was disconnected and not available or something weird like that. Funny thing is that I had called right back, so how can a disconnected number even call me?
this is probably not a "real" number but spoofed (faked) for caller ID purposes. The point of the call is to trick people into pressing a number so that they can use your account to make international or toll calls.
Most people are familiar with automated systems in which callers have to press "1" for English or "2" for spanish (something to that affect). The call is in spanish to make you assume that you must press a number to have them continue in English.
They are preying on the fact that you are familiar with automated systems, but unfamiliar with spanish. If you get a call you dont understand, just hang up. If it is important, they will leave a message in English.