Is 103 A Prime Number?

Yes it is, a prime number can only be divded evenly by itself and 1, see list of first 1000 primes here... primes.utm.edu

You can check by dividing by all of the primes less than the square root. (If the square root is an integer, it is not prime.) You know the square root of 103 is between 10 (10²=100) and 11 (11²=121), so you only need to try division by 2, 3, 5, and 7.

Division by 2, 3, and 5 can be done "by inspection." 103 is not divisible by 2, because is doesn't end in an even number. It is not divisible by 3 because the digits don't add to something divisible by 3. It doesn't end in 0 or 5, so it is not divisible by 5. That leaves 7 as a divisor to test. You can perform the long division in your head: 10-7 = 3; 33/7 is not an integer. Therefore, 103 is prime.

Yup it is a prime number.