I assume you mean 1280x720?
I ask this because...well...as long as it is 16:9 (1.78:1)...you can view in 720p at well...any resolution that is 16:9...Right now, I have a small youtube window open...on my phone...running at 1080p...yes it is full screen...but seeing as that screen is tiny...it is...well...tiny?
720p = 720 horizontal scan lines (Not a depiction of actual size as such)