  The main concepts of the recently developed approach to singular problems of
quantum mechanics are extended to the Dirac particle in the Coulomb field of a
point-like nucleus with its charge Z>137. The reflection and transmission
coefficients, which describe, respectively, the reflection of electron by the
singularity and its falling onto it, are analytically calculated, using the
exact solutions of the Dirac equation. The superradiation phenomenon is found.
It suppresses the widely discussed effect of spontaneous electron- positron
pair creation.
