Prime Factorization

main.js

/**
 * Gets all the prime factors of a given number.
 * @param {number} number for which to get all prime factors.
 * @param {!Array<number>=} allDivisors List of all prime factors.
 *  This parameter is not meant to be sent when called by a user, but
 *  it is used for the recursive nature of the implementation.
 */
const getPrimeFactors = (number, allDivisors = []) => {
  if (number < 2) throw new Error('getPrimeFactors only accepts numbers greater than 1.');
  const maxDivisor = Math.ceil(Math.sqrt(number));
  for (let divisor = 2; divisor <= maxDivisor; divisor++) {
    if (number % divisor === 0 || number % divisor === -0) {
      allDivisors.push(divisor);
      const newNumber = number / divisor;
      return findDivisor(newNumber, allDivisors);
    }
  }
  if (number != 1) allDivisors.push(number);
  return allDivisors;
};