Is 2 the Only Even Prime Number?

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mathdad
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I know that 2 is an even number. I equate prime numbers with odd numbers. Why is 2 a prime number when it is listed in a group of odd numbers? Is 2 the only, even prime number? Why?
 
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RTCNTC said:
I know that 2 is an even number. I equate prime numbers with odd numbers. Why is 2 a prime number when it is listed in a group of odd numbers? Is 2 the only, even prime number? Why?

A prime number is a natural number greater than 1 that only has 1 and itself as factors. Since 2 is greater than 1 and only has 1 and 2 as factors, it is therefore a prime number. It is the only even prime number because all other even numbers also have 2 as a factor. :)
 
RTCNTC said:
I know that 2 is an even number. I equate prime numbers with odd numbers.
Well, there's your problem! You cannot "equate prime number with odd numbers". For one thing, the odd number, 9, is NOT prime!

Why is 2 a prime number when it is listed in a group of odd numbers? Is 2 the only, even prime number? Why?
Do you know what prime numbers are? What is your definition of "prime number"?
 
MarkFL said:
A prime number is a natural number greater than 1 that only has 1 and itself as factors. Since 2 is greater than 1 and only has 1 and 2 as factors, it is therefore a prime number. It is the only even prime number because all other even numbers also have 2 as a factor. :)

Thank you for your help.