JavaScript: Check whether the provided integer is a prime number or not

JavaScript fundamental (ES6 Syntax): Exercise-191 with Solution

Write a JavaScript program to check if the provided integer is a prime number or is not.

• Check numbers from 2 to the square root of the given number.
• Return false if any of them divides the given number, else return true, unless the number is less than 2.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const isPrime = num => {
  const boundary = Math.floor(Math.sqrt(num));
  for (var i = 2; i <= boundary; i++) if (num % i === 0) return false;
  return num >= 2;
};

console.log(isPrime(11));
console.log(isPrime(17));
console.log(isPrime(8));

Sample Output:

true
true
false

Pictorial Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-191-1 by w3resource (@w3resource) on CodePen.

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