Found a way

Dim ws As Worksheet
Dim lngPageNumber As Long
Dim hPgBrks As Long

lngPageNumber = 0

For Each ws In ActiveWindow.SelectedSheets
hPgBrks = 0
If ws.HPageBreaks.Count = 0 Then
hPgBrks = 1
Else
hPgBrks = ws.HPageBreaks.Count + 1
End If
lngPageNumber = lngPageNumber + hPgBrks
ws.Range("Z1").Value = lngPageNumber
Next ws