In fact numbers stored in the native integer format may be stored
       either in the signed native form, or in the unsigned native form.  Thus
       the limits for Perl numbers stored as native integers would typically
       be -2**31..2**32-1, with appropriate modifications in the case of
       64-bit integers.  Again, this does not mean that Perl can do operations
       only over integers in this range: it is possible to store many more
       integers in floating point format.