gistfile1.txt

constant @primes = 2, 3, -> $n is copy { repeat { $n += 2 } until $n %% none @primes ... * > sqrt $n; $n; } ... *;

multi factors(1) { 1 }
multi factors(Int $remainder is copy) {
  gather for @primes -> $factor {
    if $factor * $factor > $remainder {
      take $remainder if $remainder > 1;
      last;
    }

    # How many times can we divide by this prime?
    while $remainder %% $factor {
        take $factor;
        last if ($remainder div= $factor) === 1;
    }
  }
}

say factors(536870911).perl;