What is "illegal number"

n. (context legal English) a number that represents information which is illegal to possess, utter or propagate. Any information that can be represented in binary format is, ''ipso facto'', representable as a number, and therefore if the information itself is illegal in some way, the pure number itself may be called illegal.(cite web author=Phil Carmody title=An Executable Prime Number? url=http://asdf.org/~fatphil/maths/illegal.html accessdate=2007-05-08 quote=Maybe I was reading something between the lines that wasn't there, but if arbitrary programs could be expressed as primes, the immediate conclusion is that all programs, including ones some people wished didn't exist, can too. I.e. the so called 'circumvention devices' of which my previous prime exploit was an example.)(cite news author=Thomas C Greene title=DVD descrambler encoded in ‘illegal’ prime number work=The Register date=2001-03-19 url=http://www.theregister.co.uk/2001/03/19/dvd_descrambler_encoded_in_illegal/ quote=The question, of course, is whether an interesting number is illegal merely because it can be used to encode a contraband program. accessdate=2007-05-08)(cite web url=http://primes.utm.edu/glossary/page.php?sort=Illegal title=The Prime Glossary: illegal prime quote=The bottom line: If distributing code is illegal, and these numbers contain (or are) the code, doesn't that make these number [sic] illegal? accessdate=2007-05-09)

An illegal number is a number that represents information which is illegal to possess, utter, propagate, or otherwise transmit in some legal jurisdiction. Any piece of information is representable as a number; consequently, if communicating a specific set of information is illegal in some way, then the number may be illegal as well.