Check to see if a number is prime (generated with some help from ChatGPT)

isPrime.js

// Create an object to store the results of previous calculations
const primeCache = {
  2: true,
  3: true,
  5: true,
  7: true,
  11: true,
  13: true,
  17: true,
  19: true,
  23: true,
  29: true,
  31: true,
  37: true,
  41: true,
  43: true,
  47: true,
  53: true,
  59: true,
  61: true,
  67: true,
  71: true,
  73: true,
  79: true,
  83: true,
  89: true,
  97: true,
};

const hasNonPrimeRemainder = (num) => {
  const remainders = [2, 4, 5, 6, 8, 0];

  if (remainders.includes(num % 10)) {
    return true;
  }

  return false;
};

const isNotAnInteger = (num) => {
  return num % 1 !== 0;
}

function isPrime(num) {
  // Check if the result of the calculation has been memoized
  if (primeCache[num]) {
    return primeCache[num];
  }

  if (isNotAnInteger(num) || 
    num < 2 ||
    hasNonPrimeRemainder(num) ||
    num % 2 === 0 || 
    num % 3 === 0 || 
    num % 5 === 0
  ) {
    primeCache[num] = false;

    return false;
  }

  // Check if the number is divisible by any other number up to the square root of the number
  let i = 5;
  while (i * i <= num) {
    if (num % i === 0 || num % (i + 2) === 0) {
      primeCache[num] = false;

      return false;
    }

    i += 6;
  }

  // If the number passes all tests, it is a prime number
  primeCache[num] = true;

  return true;
}