Q: Can I delete or hide the page numbers Sibelius creates by default?
A: Page numbers in Sibelius are a special type of Text Style which cannot be selected directly.
As such, they cannot be hidden or removed in the “normal” way, e.g. selected and deleted like other “System”text – for example, Tempo mark or a regular Header or Footer. (You might wish to hide page numbers when creating a worksheet, for example.)
They can easily be hidden, however. In Sibelius 7 and later, choose “Page Number Change” in the Numbering group of the Text tab and then select “Hide page numbers”:
In Sibelius 6, this dialog is found in Create > Other > Page Number Change.
A German version of this post („Seitenzahlen ausblenden”) is available here.