perl -ne 'undef $/; $\="\n"; 
(($count = $1) =~ s/.*\Count\s*(\d+).*/\1/ && 
$pages < $count ? $pages=$1 : 1) 
while s/(<<[^<]*\/Type\s*\/Pages[^>]*>>)//; 
print $pages' somefile.pdf

##</code><code>##

23 0 obj
<< /Type /Pages
   /Resources 76 0 R
   /MediaBox [ 0 0 595 842 ]
   /Kids [ 24 0 R
            // and so on
           ]
   /Count 11
>>
endobj