


It is used to find all prime numbers except 2 and 3. We can also verify the list from the list of prime numbers above. The process repeats until all the numbers on the list are either encircled or crossed out. As few multiples like 6, 12, 18, 24, 30 … are already crossed out, the remaining ones, like 9, 15, 21, 27, 33, and so on, up to 100, are crossed out now. All the multiples of 3, except 3, are crossed out.

Again, 2 and 3 are the only two consecutive prime numbers. 2 is the only even prime number, and the rest are all odd. Thus there is a total of 25 prime numbers between 1 and 100. For example, 4 is divisible by 1, 2, and 4Ī list of prime numbers from 1 to 100 is provided below for reference: Between 1 and 10 It can be divided evenly by all its factors. For example, 2 is divisible only by 1 and 2. It can be divided evenly only by 1 and the number itself. Difference between Prime and Composite Number Prime Number Similarly, 1 is also not a prime number as it has only one factor (the number 1 itself). Natural numbers greater than 1 that are not prime are known as composite numbers.Ġ is not a prime number, as it has infinite factors.
