Researchers Discover Largest Known Prime Number

Math geeks at Central Missouri State University have discovered the largest known prime number thanks to 700 computers that have spent years searching for large prime numbers. The number is 2^30402457 – 1. That's a large number. (Prime numbers in the form, "2 to the power of a prime number, minus 1," are called Mersenne primes. For example, 2³ – 1 = 7; 7 is a Mersenne prime number.)

When I worked as a math instructor at a Sylvan Learning Center, I had to teach several students to recognize any prime number less than 100. (91, by the way, is not prime; it is the product of 7 and 13.) Now I know that this exercise had a purpose: If a student develops this skill and is able to recognize an exceptionally large prime number, her or his efforts will be covered by the Associated Press.