First, no one would ever say this in real life.
But "four and twenty" is 24. So "four and twenty million" would be 24 million.
You have to know that there is an old nursery rhyme about "four and twenty blackbirds baked in a pie."
This is not a normal way to say "twenty-four" now, if it ever was in the past.
Also note that this may be a reference to "4:20" which is a code for smoking marijuana. Supposedly from a group of kids who used to indulge every day after school at this time.
Student or Learner