Factorialize a Number-Using arrays comes out NULL

JavaScript
1

Tell us what’s happening:

I tried making a function that takes a parameter, and puts every number less then the parameter up to zero and pushes it into an array(descending order). and then used a for loop to multiply each index of the array by the next index, but my return comes back null. please help.

Your code so far

function factorialize(num) {
  var arrayOfFactorial = [];
  var factorial = 1;
 for(var i = num;i > 0;i--){
   arrayOfFactorial.push([i]);
   factorial = factorial * arrayOfFactorial[i];
 } 
  
  return factorial;
}

factorialize(5);

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