Is 30 a Prime Number?

30 is not a prime number as it has more than two factors, which divides 30 without leaving any remainder.

The factors of 30 are 1, 2, 3, 5, 6, 10, 15 and 30. There are various methods to examine if a number is a prime number or a composite number.

Types of methods to find if a number is prime or composite.

• Counting divisors method

• Divisibility method

• Prime number chart method

• Prime factorization method

In the counting method, the divisors of the number are counted. 30 has 4 divisors, thus 30 cannot be a prime number as it does not satisfy the two-factor rule.

The divisors of 30 = 1, 2, 3, 5, 6, 10, 15 and 30.

 
Therefore, 30 is not a prime number. 

The divisibility method states that if a number is divisible by numbers more than two, then the number is not a prime number. The number 30 is divisible by 1, 2, 3, 5, 6, 10, 15, and 30, which makes it a composite number.

The chart of prime numbers is referred to in this method. The number 30 is checked whether it appears in the chart of prime numbers from 1 to 100.

The prime numbers are: 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.

By referring to the list, it is understood that 30 does not appear in the list.

Therefore, 30 is not a prime number.

The method of writing the number as a product of primes is the prime factorization method. 

The prime factorization of 30 is,
30 =21 × 31 × 51

Therefore, the prime factors of 30 are 2, 3, and 5.

• Prime Number: The number that has only two divisors, 1 and the number itself.

• Composite Number: Composite numbers are numbers that have more than two factors.

• Prime Factorization: Prime factorization is a method of writing all numbers as a product of prime.