If there are other such numbers, I might consider a meaning. Alone, it means nothing.
From the Sermon of Numbers, 7 is the sword which wins the crown, or the lord who bears the turning of the wheel. We already know Lorkhan is Buddha, and Dovahkiin is one avatar of seven.
My first thought, if this is 7, because it really looks like none of the daedric, was it might signify the seventh piece of the mural. Maybe it's divided in pieces, and they engraved the numbers on the front and not the back.
Boring and safe.