  It is shown that the square of the Dirac Hamiltonian with the isotropic
mass-hedgehog potential in d dimensions is the number operator of fictitious
bosons and fermions over d quantum states. This result allows one to obtain the
complete spectrum and degeneracies of the Dirac Hamiltonian with the hedgehog
mass configuration in any dimension. The result pertains to low-energy states
in the core of a general superconducting or insulating vortex in graphene in
two dimensions, and in the superconducting vortex at the topological - trivial
insulator interface in three dimensions, for example. The spectrum in d=2 is
also understood in terms of the underlying accidental SU(2) symmetry and the
supersymmetry of the Hamiltonian.
