How many mercury Apollos were there?

In the Mercury progam there were 20 unmanned launches; of these four carried monkeys (2 rhesus macaque and 2 chimpanzees); and 6 manned missions. Further missions wre planned, but were cancelled in favour of the Gemini program.

In the Apollo program there were 6 unmanned missions; and 12 manned mission, of these 6 missions landed on the moon.

In addition the four skylab missions used Apollo equipment; as did the Apollo-Soyuz mission. However these were not considered to be part of the Apollo program.