Javascript - Sum all prime numbers

optimusPrime.js

function sumPrimes(num) {
  return Array.apply(0, Array(num + 1))
    .map(function(x, y){
      return y 
  }).filter(function (i){
      return (i > 1) && Array
          .apply(0, Array(1 + ~~Math.sqrt(i)))
      .every(function(x, y){ 			
          	return (y < 2) || (i % y !== 0) 
      });
    }).reduce(function(current, previous){
  		return current + previous;
  });
}

sumPrimes(977);