I don't have the exact numbers, but the Apollo astronauts spent a lot of time in different types of simulators. For the landing crews, they had not only the computer driven Lunar Module simulators but the airborne (and very risky) "Flying Bedstead" Lunar Landing Training Vehicle (originally titled the Lunar Landing Research Vehicle) as well as mockups of the experiments and equipment they used on the lunar surface. There were also simulators for the Command Module to practice every phase of the mission from prelaunch through reentry.

These simulators were used no only to train the flight crews, but also the ground controllers. Many, many glitches they encountered on the different missions were properly simulated, including engine failures during launch, computer problems, and the like. There's no substitute for adequate emergency training, even if training for every possible scenario isn't possible. A big part of handling an emergency is recognizing it exists, then handling it smoothly under pressure. That's a lot easier to accomplish if you've seen the emergency before. Even when the emergency is one that's new, like Apollo 13, the training helps people think clearly in a crisis as they work the problem.