May Challenge - Odd

A few years ago I gave my youngest daughter a numerical Rubiks cube, a puzzle which she has since failed to complete. With a bit of fiddling I managed to get two number 9s the same way up on one side, which in a way is a little odd. If you add all the numbers on a face when the puzzle is completed you get 45 - an odd number - though if you add all the numbers up on the main face in this picture you get 52, odd that I thought it was odd surely!