I called back using *67 (which blocks your phone number to the person you're calling), and I got a Verizon error message. This leads me to believe that the call is, indeed coming from a scammer who is scrambling their phone number somehow. I've blocked the number on my iPhone, but if it's a scam, they'll find another way. I just don't answer calls from numbers I don't recognize. If someone really wants to talk to me, they'll leave a message.
en este instante ese numero me ha llamado, al descolgar he escuchado la voz de una contestadora automatica que decia: "ha recibido un mensaje para escucharlo presione 1 para borrarlo presione... " antes de que terminara la expresion colgue la llamada