I would agree that 5 is to be interpreted as an operator. If it were part of the number, then 2^6 would be QCQ5QBABQ5QCQ, but it is represented as QCQ5QBABQ5. It seems that 5 is an operator which can be modified by a number. Also, Mr. Neylon... there is one other physical constant we have (well, at least one)... the wavelength of the message itself.