The word "even" has an even number of letters, the word "odd" has an odd number of letters. Even has an even number of syllables, odd has an odd number of syllables. If you add up the values of each letter in "even", you get 46 ( 5(e) + 22(v) + 5(e) + 14(n) = 46 ), which is an even number. For the word "odd" it is 23 ( 15(o) + 4(d) + 4(d) = 23 ), which is odd. 46 is twice as much as 23. If you double any integer, regardless of whether it's even or odd, you get an even number. If you add 4 and 6 you get 10. If you add 2 and 3 you get 5. 10 is twice as much as 5.
And that's the point I stopped going down the rabbit hole while I knew I could still get out.
EDIT: I couldn't help myself. 23 is the 9th prime number, and 9 is also odd. 46 is the 16th semiprime number (a number that is the product of two prime numbers), which is even. The square root of 16 is 4, which is an even number. The square root of 9 is 3, which is odd. 4 and 3 make 43, which is Richard Petty's number. I always knew all those wins and championships weren't by accident.