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The number 1 is not a prime number. A prime number by definition is a positive integer greater than 1 that is evenly divisible by only itself and 1.

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Two is a prime number. Two is the smallest prime number and the only even prime number, since all other even numbers divide by two.

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Yes, 2 is a prime number. In fact, 2 is the only even number that is prime. A prime number is a number that has only two factors, the number 1 and itself.

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Nine is not a prime number. It is a composite number, because it has more than two factors. A prime number is only divisible by one and by itself, and nine is divisible by one and by nine, but it is also divisible by the number three.

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The number zero is not a prime number. By definition, a prime number dictates that the number must be a whole number greater in value than one and must be divisible by only itself and one.

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The number 19 is the eighth prime number. A prime number is a positive, whole number that is only divisible by one and itself. Nineteen is also the seventh Mersenne prime exponent, which is a prime number that is one less than a power of two.

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The prime factors of 12 are 2 and 3. A prime number is a number greater than 1 that cannot be divided by any number except itself and 1. Both 2 and 3 are prime factors of 12 because they are prime numbers that can be divided into 12 with nothing remaining.

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The prime factors of 6 are 2 and 3. The number 6 cannot be factorized into any other combination of prime numbers. A prime number is a whole number larger than 1 which can only be divided by 1 and itself.

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The prime factors of 30 are 2, 3 and 5. In addition to being the factors of 30, the numbers 2, 3 and 5 are also prime numbers, which means that they can only be divided evenly by either the number 1 or by themselves. The numbers 2, 3 and 5 are also the first three prime numbers.

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The prime factorization of 100 is 2^2 x 5^2, or 2 x 2 x 5 x 5. One hundred is considered a composite number because it is a positive integer divisible by at least one positive number other than 1 and 100 (itself).