Page numbers in illustrator

Would this help you?

#target illustrator

function test(){

  var doc = app.activeDocument;

  var startNum = prompt("Specify the starting index", "1");

  if(startNum == null || !startNum){

    return;

  }

  startNum *= 1;

  if(isNaN(startNum)){

    alert("Not a valid number");

    return;

  }

  var newText, thisRect;

  var pageNumLayer = doc.layers.add();

  pageNumLayer.name = "Page Numbers";

  var counter = startNum;

  for(var i = 0;  i < doc.artboards.length;  i++){

    newText = pageNumLayer.textFrames.add();

    newText.contents = counter++;

    thisRect = doc.artboards.artboardRect;

    newText.position = [thisRect[2] - 20, thisRect[3] + 20];

  };

};

test();