The number shown on enchanted items is at the back of that item. Happens with enchanted golden apples and books. Of course, this can't happens with weapons, bows and armor as they can be held one in a box!
To reproduce the problem:
1. Open inventory in creative mode.
2. Take more than one enchanted golden apples or enchanted books.
3. See the number. Its behind the enchanted golden apples or enchanted books.
Sorry for not giving screenshots. Just try reproducing it!
EDIT: This also happens with Nether star, bottle o enchanting and all items with enchanting shine i.e purplish gradient shine flowing over the items.