Call and hang up - at 6:04 AM! However, thanks to warning on this site of calls in the middle of the night, I had my phone on "silent mode" and so was not awakened. Scum!
Called at 4:20 AM but I had set my Digitone device not to ring the phone at those hours unless the call is from family or certain emergency numbers so I wasn't awakened. Now the number is blocked and i won't be hearing from it again.