I'll add my stories to the 2 brother comments, in my prepa my best friend was by far the best in class. He did the 2 year program in chemistry in the first 2 months by himself. He arrived once in exams after a full night of re-reading the 3 LOTR books and still nailed the best grade effortlessly. And to his own admission, he was far from the most productive / smarter guys he knew.
I remember listening to him and a teacher, the teacher would give some anecdotes on what he's seen at the ENS. People reciting world chess championship games at night to fall asleep. Reading massive math books (1000+ pages) in an afternoon. Another story I heard in a different context from another teacher, math students were assigned a python project, after an introductory course. They never did any programming before. One student wrote 300 LoC in a single function and showed it to the teacher. It didn't have a main function, so the teacher asked him how he tested it. The student didn't know what he was talking about. They added what's needed to run the function and it worked.
So, it still begs the question... "How ?" Or, more precisely: "How the f... ?"
Clearly this goes beyond "Grit" [1], here, right ? (Those people do not seem like they have to coerce themselves into focusing that much.)
Is there a known (somewhat rigorous or not) study of those "super geniuses" ? I know that the "memory champions" are covered in "Moonwalking with Einstein" [2] ; but that seems like a different beast...
[1] https://www.simonandschuster.com/books/Grit/Angela-Duckworth... [2] https://www.goodreads.com/book/show/6346975-moonwalking-with...
Ah, I wouldn't know of any actionnable way to unlock this for yourself unfortunately. I think those people are gifted. There is definitely research (and documentaries around that research), you can look for Julian Stanley "Quick learners" or Maryam Mirzakhani and there are of course plenty of it. But again, it's not actionnable to watch a 13yo solve a very hard problem in 4 different ways in 20 minutes.
Unfortunately I think it is as much a curse as it is a gift. One of my parents' friend is a math researcher. He is not at the absolute end of the spectrum, but he is the kind of people who will write on the bathroom walls because he has an idea NOW and it cannot wait a minute to explore. He forces himself to do competitive cycling and can't enjoy more casual hobbies because if he does not spend 100% of his energy and focus to something, his brain will just do math.