Project Euler problem 7

6.js

/*
http://projecteuler.net/problem=7

By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.

What is the 10 001st prime number?
*/

var findPrime = function findPrime(num) {
  var t0 = performance.now();
  var count = 2;
  test:
  for (var test = 5; count !== num; test += 2) {
    var divisor = Math.ceil(Math.sqrt(test)) % 2 ? Math.ceil(Math.sqrt(test)) : Math.ceil(Math.sqrt(test)) - 1;
    for (divisor; divisor > 1; divisor -= 2) {
      if (!(test % divisor)) {
        continue test;
      }
    }
    count++;
  }
  return {prime: test - 2, time: performance.now() - t0};
}

findPrime(10001);