Publishing this number is illegal in the USA, because it's something of a commercial secret used to protect copyrights:
or, decimal if you prefer:
or get it on a t-shirt (from the USA).
This number is the HD-DVD encryption key. If you know how to do it, it's possible to decrypt HD-DVD disks with this key, making them copyable, downloadable or whatever. As you might expect, there are lawsuits abound over the pond at the moment.