hard code large hex value throws error in C# : <p>ulong va = 0xffffffe0‬;</p>

<p>This throws the below errors:</p>

<pre><code>Error   1   Unexpected character '‬'    
Error   2   Invalid expression term ''  
Error   3   ; expected  
Error   4   Only assignment, call, increment, decrement, await, and new object expressions can be used as a statement
</code></pre>

<p>why is it so? How can i fix?</p>
