The temperature of a Schwarzschild black hole, according to Hawking, is hbar time c^3, divided by 8 π G k_{B} M. Here hbar is Planck's constant, c is the speed of light, G is Newton's constant, k_{B} is Boltzmann's constant, and M is the mass of a black hole. This gives about 6 one-hundred millionths of a Kelvin, divided by the mass of the black hole in solar mass units.
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