[Sorting a String numerically 1-550]

I have the following code in my PHP and would like it to sort the Lot Numbers numerically some numbers have letters after the i.e 220, 220A , 220B so I cant use (int) which sorts the numbers without letters if I use (string) it sorts the numbers 1, 10,100 etc. Any help would be appreciated.

 

The current code is

 

$lot_number = php_safe((string)$row['lot_number']);