Extended digit notation allows you to express  unsigned  integer
  values in terms of a base number.  VSI Pascal accepts numbers in
  bases 2 through 36.

  Syntax:

     [[ + | - ]] base-number#[[']]extended-digit[[']]

  The 'base-number' specifies the base of the number.

  The 'extended-digit' specifies the notation that is  appropriate
  for the specified base.

  You can use extended-digit notation in the same way you use  the
  conventional    unsigned    integer    notation,   except   that
  extended-digit values cannot be used as labels.

  VSI Pascal allows the  use  of  spaces  and  tabs  to  make  the
  extended-digit notation easier to read.  To use spaces and tabs,
  enclose the extended digit in single quotation marks (' ').  The
  following  are  unsigned  integer  values  in the extended-digit
  notation:

       16#80000000
       16#'8000 0000'
       16#'FFFF FFFF'