Well, once you've gotten a match with the above regex, then all you need to do is delete the commas.

  $num = '654,321';
  if ( $num =~ /^\d{1,3}(,\d{3})*$/ ) {
    $num =~ y/,//d; # delete commas
  }
  else {
    # not a conforming number
  }
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jdporter
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