I'm sorry, but how exactly is this "amazing"? That you can find some bits to append to a number such that it becomes prime is rather obvious, given that there are an infinite number of primes and (probabilistic) primality tests are readily available. As other have pointed out, this is no more interesting than the fact that adding a "1" bit yields an odd number.
And what's the point? Yes, illegal information can be encoded as bits, those bits interpreted as numbers, and then you can apply transformations to those numbers. So what?
And what's the point? Yes, illegal information can be encoded as bits, those bits interpreted as numbers, and then you can apply transformations to those numbers. So what?