According to Hawking's formula for black hole evaporation
A black hole with a mass of just 174 million tonnes (china burns more mass in coal each year) would not evaporate for over 14 billion years, the time elapsed from the Big Bang to the present. That estimate assumes that no additional matter was sucked into the black hole during that time period. How likely is that? I would suggest that even smaller black holes would have a good chance of outlasting the present age of the universe. That's if there is even a natural mechanism to create such a low-mass black hole.