11 million, according to the Ministry of Truth.
We do not have to remove 19 million, or even 400,000 criminals. All we have to do is cut off their welfare and other government benefits, prosecute their employers, and charge those who are deported for the government cost of deportation. After a few thousand, the rest will move home on their own rather than lose any assets they may have accumulated.
Bonus: Those who are deported should be fingerprinted and permanently barred from reentry to the United States.