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What is the format for base64 numbers?
The easiest way to convert it is probably to convert the decimal to binary and then group the bits in sixes. If your number is a BigInteger, you can probably get its octal or hexadecimal representation as a String from one of its methods.
Joined: Jun 05, 2012
The requirements is to compress 20-22 digit base 10 to 12 digit Base64. For example;
Before convert (Base10): 1234567890123456789012
After convert (Base64): Niww28wSbO9k
Joined: Oct 13, 2005
. . . and what do the different letters represent? Which represents 62 and which 63?
What have you tried?