Re: Why 21 million bitcoins? Why was ~that~ number chosen?

It's a good thing Satoshi didn't go much higher, because 21 * 10^14 is breaching on what a signed 64 bit integer can hold.

A signed 64-bit integer will go up to about 9.2 * 10¹⁸, much larger than the 2.1 * 10¹⁵ bound.