Prime numbers

• The first ten prime numbers are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29.
• A prime number has no whole-number factors other than 1 and itself.
• 9 is not a prime number because 3 X 3 = 9 .
• 7 is a prime number because only 1 and 7 divide 7 evenly.
• The larger a number is, the harder it is to tell if it is prime.
• No one has yet found a pattern or formula for counting indefinitely by primes.