Caribou calves weigh about 13 pounds at birth. Is this number 13 a prime or composite number?
Let’s define prime and composite numbers. A prime number is a number that is only divisible by itself and one. A composite number is a whole number that is made by multiplying other whole numbers together. It’s common to memorize the list of the first few prime numbers: two, three, five, seven, 11, 13, 17, 19, 23, and 29.
13 is on the list. It’s a prime number because it’s only divisible by one and itself. 13 is a prime number.