Returns the maximum allowed value for internal whole numbers used e. g. as arguments to built-in functions, as the right-hand operand of the power (**) operator, or as the values of exprr and exprf in a DO or LOOP instruction.

See also methods internalMinNumber and internalDigits.

say .RexxInfo~internalMaxNumber  -- 999999999          /* 32-bit addressing mode */
say .RexxInfo~internalMaxNumber  -- 999999999999999999 /* 64-bit addressing mode */