Numbers: Integers
Prime numbers
We have seen that we cannot factorize the number #7#. Numbers with this property are part of a special group of numbers with an important role in mathematics.
Prime number
The integer #5# has exactly two divisors, namely #1# and #5#.
The integer #13# has exactly two divisors, namely #1# and #13.#
The numbers #5# and #13# are examples of prime numbers.
A prime number is a positive integer which has exactly two divisors: #1# and itself.
The list of prime numbers begins as follows: \[\begin{array}{c}
2,3,5,7,11,13,17,19,23, 29,31, \\
37,41,43, 47, 53, 59, 61, 67, 71, 73, \\
79, 83, 89, 97, 101, 103, 107, 109,113, \\
127, 131, 137, 139, 149, 151, 157 \ldots \end{array}\]
No
No, #100# has more than #2# divisors, namely #1,2,4,5,10,20,25,50,100#.
No, #100# has more than #2# divisors, namely #1,2,4,5,10,20,25,50,100#.
Unlock full access
Teacher access
Request a demo account. We will help you get started with our digital learning environment.
