A Prime (Number) Problem
Riddles are little poems or phrases that pose a question that needs answering. Riddles frequently rhyme, but this is not a requirement.
There is a number that fulfills all of the following criteria/rules:
1. It is prime.
2. It is a whole number.
3. It is greater than or equal to 1.
4. If you double it, square it, and add itself to it, you get the same single digit even number answer for each operation.
What is this number?
HintThe "single digit even number" mentioned in the 4th criterion/rule is equal to the number of criteria that the "mystery number" fulfills.
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Answer
2.
2 is prime.
2 is a whole number.
2 is greater than 1.
2 x 2 = 4.
2 ^ 2 = 4.
2 + 2 = 4.
4 is a single digit even number, and is the answer for all the above operations.
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Comments
guelmik
Aug 29, 2010
 too easy... 
racoonieboy
Aug 30, 2010
 N*N=N^2
N*N=N^N
Therefore, N=2. 
racoonieboy
Aug 30, 2010
 Erm... I made a mistake on above comment. It said square. (What was I thinking?) I meant to say:
N*2=N+N
N*N=N+N
Therefore, N=2 
rlc327
Aug 30, 2010
 I wasn't planning on making it difficult, just exploiting a little mathematical "quirk". 
cutieluck
Aug 30, 2010
 it wuz pretty easy but it wuz nice to kno (: 
Stack1607
Sep 02, 2010
 easy but nice one! 
kwelchans
Sep 03, 2010
 Doubling a number is the same as adding the number to itself. Therefore, the 4th criterion is redundant. 
rlc327
Sep 03, 2010
 I'm perfectly aware that the 4th criterion is redundant. 
orion
Dec 28, 2010
 TOOK me a minute but i got it 
zizorizo
Jan 17, 2011
 we took that one in KG lol , just type " the only even prime number " 
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