  In this work we present a simple, approximate method for analysis of the
basic dynamical and thermodynamical characteristics of Kerr-Newman black hole.
Instead of the complete dynamics of the black hole self-interaction we consider
only such stable (stationary) dynamical situations determined by condition that
black hole (outer) horizon circumference holds the integer number of the
reduced Compton wave lengths corresponding to mass spectrum of a small quantum
system (representing quant of the black hole self-interaction). Then, we show
that Kerr-Newman black hole entropy represents simply the quotient of the sum
of static part and rotation part of mass of black hole on the one hand and
ground mass of small quantum system on the other hand. Also we show that
Kerr-Newman black hole temperature represents the negative value of the
classical potential energy of gravitational interaction between a part of black
hole with reduced mass and small quantum system in the ground mass quantum
state. Finally, we suggest a bosonic great canonical distribution of the
statistical ensemble of given small quantum systems in the thermodynamical
equilibrium with (macroscopic) black hole as thermal reservoir. We suggest
that, practically, only ground mass quantum state is significantly degenerate
while all other, excited mass quantum states are non-degenerate. Kerr-Newman
black hole entropy is practically equivalent to the ground mass quantum state
degeneration. Given statistical distribution admits a rough (qualitative) but
simple modeling of Hawking radiation of the black hole too.
