(PHP 8 >= 8.2.4)
GMP::__construct — Create GMP number
Creates a GMP number from an integer or string.
numbase2 and 62.
      For bases up to 36, case is ignored;
      upper-case and lower-case letters have the same value.
      For bases 37 to 62,
      upper-case letter represent the values 10 to
      35 and lower-case letter represent the values
      36 to 61.
     
     
      If base is 0 then the actual
      base is determined from the leading characters of num.
      If the first two characters are 0x or 0X,
      the string is interpreted as a hexadecimal integer.
      If the first two characters are 0b or 0B,
      the string is interpreted as a binary integer.
      If the first two characters are 0o or 0o,
      the string is interpreted as an octal integer.
      Moreover, if the first character is 0 the string
      is also interpreted as an octal integer.
      In all other cases, the string is interpreted as a decimal integer.
     
    