Trying to find factors of a number in JS

Question

I am just starting JS, and understand the concept of finding a factor. However, this snippet of code is what I have so far. I have the str variable that outputs nothing but the

Answer 1

here is a performance friendly version with complexity O(sqrt(N)). Output is a sorted array without using sort.

var factors = (num) => {
let fac = [], i = 1, ind = 0;

while (i <= Math.floor(Math.sqrt(num))) {
  //inserting new elements in the middle using splice
  if (num%i === 0) {
    fac.splice(ind,0,i);
    if (i != num/i) {
      fac.splice(-ind,0,num/i);
    }
    ind++;
  }
  i++;
}

//swapping first and last elements
let temp = fac[fac.length - 1];
fac[fac.length - 1] = fac[0];
fac[0] = temp;

// nice sorted array of factors
return fac;
};
console.log(factors(100));

Output: [ 1, 2, 4, 5, 10, 20, 25, 50, 100 ]