Android : Android : CSV not storing values in normal format

I am trying to store values in csv file. But it is storing all those values in exponential format.

FileOutputStream fos;

   try {  
        File dir = new File("/sdcard/");  
        boolean b = dir.mkdir();
        File myFile = new File(dir, filename); 
        myFile.createNewFile();  
        FileOutputStream fOut = new FileOutputStream(myFile); 
        OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut);
        for (String s : arrayListDGId) {
           myOutWriter.append(s + "\n"); 
        }                     
          myOutWriter.close();  
          fOut.close(); 

These are the example values of arraylist 10989808,8768762,76876787. But it stores/converts those values in exponential form like 1E+9, 8E+8 & so on format. I want to store those in there normal/original format. Plz help me