Node.js lodash max() get largest prime factor

/* Program 3: Find a largest prime factor for 600851475143 */
let lodash=require('lodash');
let prime = [1], max = 600851475143, k=1;
function find_prime(max) {
    for(let i=2; i < max/2; i++) {
    let j=2//w  w  w .  ja  va 2  s. co m
    for(; j<i; j++) {
        if(i % j == 0) {
            break
       }  
    }
    if(max%i == 0 && i==j) {
        prime[k++]=i;
    }
  }
}
find_prime(max);
console.log(lodash.each(prime))
console.log("Largest prime factor for: "+max+ " is:"+lodash.max(prime))