Question: 1 and 2 is prime number or not?
Answer: A natural number (i.e. 1, 2, 3, 4, 5, 6, etc.) is called a prime number (or a prime) if it has exactly two positive divisors, 1 and the number itself. That's the definition. So 2 is prime because it has exactly two positive divisors: 1 and 2. And 1 is not prime because it has only one positive divisor: 1.