1024.

One plus one was two, two plus two was four, four plus four was eight, eight plus eight was sixteen, sixteen plus sixteen was thirty-two, thirty-two plus thirty-two was sixty-four, sixty-four plus sixty-four was one hundred and twenty-eight, one hundred and twenty-eight plus one hundred and twenty-eight was two hundred and fifty-six, two hundred and fifty-six plus two hundred and fifty-six was five hundred and twelve, five hundred and twelve plus five hundred and twelve was one thousand and twenty-four, and that was what he had.