I've received at least 1 call from this number on my cell phone a day for the past week - sometimes multiple times a day.  I've answered it a few times and the caller just hangs up.  If I call the number back, it rings once then goes to a busy signal, or says my call cannot be completed as dialed.  No idea who this is, but seems suspicious to me.  Be wary if you receive a call from this number.