It's 230 on my phone, then you have to choose option 1 and they send the text. I'm not aware of any limitations of it's use, but there probably are.
I really have no idea on international charges. They offer various added packs to reduce the charges, and the prices start at 31.8 cents per minute, but I guess with no extra subscriptions this would be considerable higher. It might be worth popping into a movistar shop and asking them what options they currently have.