Is 1009 a Prime Number?

The number 1009 is indeed considered as a prime number because it has only two divisors, which are the number one and itself. They have no other factors.

A number is said to be a prime or not a prime only when certain conditions are met. To find those there are methods to perform and when the conditions are met only the numbers are categorized as prime and composite numbers.

The methods to check any numbers are as follows:

• Count Divisor Method

• Divisibility Test

• Prime Number Table

• Prime Factorization
   

Counting divisors method refers to a type of method where we count the number of divisors of a particular number to find out whether the number is a prime number or not.

If we look at 1009 we can see that it has only 2 divisors which are 1 and 1009 . Since 1009 has only 2 divisors, it is a prime number.
 

In this test, we try to find out the prime numbers that divide the number without leaving any reminder.

Hence, we can see that there are no prime numbers that are able to easily divide 1009 without leaving any remainder. Hence, this proves that 1009 is a prime number.
 

This is a rather simple method where we write down all the prime numbers until we cross the required number, for example let's write down all the prime numbers from 1 to 1009. 2, 3, 5, 7…. 991, 997, 1009. From looking at the above list, we can see that 1009 is a prime number.
 

Prime factorization is a method where we represent a composite  number based on the factors of  two prime numbers.

In this case, the prime factors of the number 1009 are none, hence it is a prime number.
 

• Divisibility Test: It refers to a method where we can check if a number is divisible by any prime number. 

• Prime Factorization: Multiplying two prime numbers to get one number is called prime factorization 

• Composite Number :  When more than two numbers can divide a number, it is called a composite number.