Prime Number

Definition

Prime Number in plain English

A prime number is a whole number bigger than 1 that can't be split evenly into a group of smaller equal piles except the trivial ones, its only divisors are 1 and the number itself. So 7 is prime (nothing but 1 and 7 divides it), but 12 isn't because 2, 3, 4, 6 all go in cleanly. Primes are the 'atoms' of numbers: every other whole number is built by multiplying primes together, which is why they matter so much in math. Note that 1 itself doesn't count as prime, by definition.

Learn these first

• Composite Number

Related GMAT terms

• Absolute Value
• Arithmetic Mean
• Composite Number
• Discrete Data
• Discriminant
• Domain
• Exponent
• Factorial
• Greatest Common Divisor (GCD)
• Independent Events