FCC intermediate algorithm challenges - Sum All Primes

gistfile1.txt

function sumPrimes(num) {
  // stores num for later addition to sum of primes
  var originalNum = num;
  // array that will store the prime numbersof the array
  var primeArrayEnd = [];
  // finds what primes is num divisible by (it should)
  function isPrime(num) {
    var primeArray = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997];
    // loops that runs until i is not less than i
    for (var i = 0; i < num; i++){
      // if num is prime, return num 
      if(num == primeArray[i]){
        // and push that number to primeArrayEnd
        primeArrayEnd.push(primeArrayEnd[i]);
        num = primeArray[i];
      }
      // if num is divisible by any of the primes and gives 0, do this
      else if(num % primeArray[i] === 0){
        // pushes the prime number it is equal to to the array of primes to Sum
        primeArrayEnd.push(primeArray[i]);
        // num = previous num divided by the prime it is equal to
        num = num / primeArray[i];
        

        
      }
      return primeArrayEnd;
    }
  }
  // sums the array of primes
  var sumOfPrimes = primeArrayEnd.reduce(function(a, b) { return a + b; }, 0);
  // sums the sum of numbers with the original inputted num
  var total = sumOfPrimes + num;
  return total;
}

sumPrimes(17);