how to move a page number in front of an image

Hello albertlini,

This can be done by chosing to move the image to the back via the Arrange tab.

Move an object to the very top or bottom of the stack: Click Front, or click Back.

Pages Help - Layer, group, and lock objects
http://help.apple.com/pages/mac/5.5/#/tan5eab46568

Cheers,

Allen

Unfortunately, in Pages 5, the header, footer and document body are behind the "stack" in your Help document. The only way to move an image behind a page number in a header or footer is to move it to the Section Master, which can be a problem if you can't make the page a separate section and you don't want the image to reappear on every page.

For the one page solution, you could duplicate the page number in a text box in front of the image.