check if a string's first 16 char is a number
<p>I'm storing some files in database which has filename like <strong>1839341255115211butterflies.jpg</strong>.I need to show this filename to the user as <strong>butterflies.jpg</strong>.I need to remove the first 16 digit and then show the filename.Added to it I also have few filenames which don't have this 16digit addition prior to the filename.Now my question is how do I identify if this string has 16digit numeric value prior to the filename, based on it remove the 1st 16digit and display just the filename.  I'm aware of how to remove the first 16digit and retrive the filename but  need help on how to identify  a string that has 16digit.</p>

<p>Any suggestion is much appreciated.</p>
