IQ is defined to be a normal distribution with mu = 100 and sigma = 15, so “IQ 220” means ‘99.9999999999999th percentile¹’; if more than a person in 10^15 gets such a score, then the test is miscalibrated. (But most tests are, beyond a few standard deviations away from the mean.)

1. I didn't count the nines, I just copied and pasted the output of pr norm(8) in gnuplot and moved the decimal point.