Base36

Base36 is a binary-to-text encoding scheme that represents binary data in an ASCII string format by translating it into a radix-36 representation. The choice of 36 is convenient in that the digits can be represented using the Arabic numerals 0–9 and the Latin letters A–Z (the ISO basic Latin alphabet).

Each base36 digit needs less than 6 bits of information to be represented.

Conversion
Signed 32- and 64-bit integers will only hold at most 6 or 13 base-36 digits, respectively (that many base-36 digits can overflow the 32- and 64-bit integers). For example, the 64-bit signed integer maximum value of "9223372036854775807" is "1Y2P0IJ32E8E7" in base-36. Similarly, the 32-bit signed integer maximum value of "2147483647" is "ZIK0ZJ" in base-36.

Standard implementations
The C standard library since C89 supports base36 numbers via the strtol and strtoul functions

In the Common Lisp standard (ANSI INCITS 226-1994), functions like  support a radix of 2 to 36.

Java SE supports conversion from/to String to different bases from 2 up to 36. For example, and

Just like Java, JavaScript also supports conversion from/to String to different bases from 2 up to 36. 

PHP, like Java, supports conversion from/to String to different bases from 2 up to 36 using the base_convert function, available since PHP 4.

Go supports conversion to string to different bases from 2 up to 36 using the built-in, and   functions,  and conversions from string encoded in different bases from 2 up to 36 using the built-in  , and   functions.

Python allows conversions of strings from base 2 to base 36.