Can a theme name be started with a number? Can I start a theme name with a number? For example: "123go"

Does Drupal recognize folders &amp; files that start with it?

Does it work in the temple.php as the start of a function?
oh, got it- "A valid function name starts with a letter or underscore, followed by any number of letters, numbers, or underscores." 

php.net/manual/en/functions.user-defined.php

That answers that question. Don't start a theme name with a number because it can't be used as a function in template.php