6. "Which number is the first prime number?" "Oh, that's an easy one, it's number one!" "Sorry, wrong number." "Huh? I have always thought that 1 is the first prime number..."
Which number is actually the first prime number?

*From Quiz Sorry, Wrong Number*
Answer:

**2**
In the fields of real analysis and discrete mathematics, a prime number is defined as a number that is greater than 1 and has no positive divisors other than 1 and the number itself. So, by this definition, 1 is not a prime number. The divisors of 2 are 1 and 2. So 2 fits the description of a prime number. The next number, 3, also fits the criteria and hence, is also a prime number. The divisors of the next number, 4, are 1, 2, and 4. Using the definition given, 4 is not a prime number. It is a composite number from the fact that 4 = 2 x 2.