For an object heavier than the Earth, 1g radius will be greater than the radius of Earth. For 56 Earth masses that’s sqrt(56) times bigger = 48000km.
A 56 Earth mass black hole will take 5.5e55 years to evaporate according to this calculator. A 100kg black hole (more close to what Richard used to be) is much smaller than the nucleus of an atom and will evaporate in 0.05 nanoseconds.
Curiously there was a paper recently that calculated that even if there was a small black hole in the center of the Sun, it would take millions of years for it to grow, because the aperture is so small not much can fit through, and the infalling gas heats up so much as to repel the rest, creating an internal hot bubble.
Your mistake is thinking Earth is 6km in radius! :D 6km is how far you walk in an hour. Either you think Earth 1000 times too small or kilometer 1000 times too big.