My guess (which is more than a guess :P) is that "number" is some sort of ID.
When working on the script editor of my FF6 SDK, I found that if you copy [number, title, compressed_code] somewhere else in your array and change only "compressed_code", your code will be changed in every scripts with the same "number". I've discovered this when implementing copy/paste functions to the editor.
This "number" is a big one and I don't know why. Changing it makes your entry uniq.
To fix this in my editor, I simply randomize a new number for my newly copied script, but I'm not sure if it's the right way to do it...