FreeCodeCamp: Intermediate Algorithm Scripting: Sum All Primes

Sum all the prime numbers up to and including the provided number.
A prime number is defined as a number greater than one and having only two divisors, one and itself. For example, 2 is a prime number because it's only divisible by one and two.
The provided number may not be a prime.

My solution using another function to test if number is prime:
(FreeCodeCamp used recursion)
function primeNumber(num) {
  for (let i = 2; i < num; i++) {
    if(num % i === 0) return false;
  }
  return true;
}

function sumPrimes(num) {
//Greater than 1
//Prime is only divisible by 1 and itself
let allArr = [];
let primeArr = [];
for ( let i = 2; i <= num; i++) {
allArr.push(i);
}
for (let i = 0; i < allArr.length; i++) {
if (primeNumber(allArr[i]) === true) {
primeArr.push(allArr[i]);
}
}
return primeArr.reduce((a,b) => a+b);
}

sumPrimes(10);

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