46910...23129 (92-digits)

This number is a composite.

                                                    46 9101415212 2252633343
5383946495 1555758626 5697477828 5868791939 4951061111 1511811912 1122123129

Concatenating the first 43 semiprimes gives a 92-digit semiprime. This is the largest known example as of 1 February 2005. The question of which primes occur in concatenated consecutive semiprimes is not yet known. [Post]