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September 1, 2023

What are Prime Numbers? There are lots of definitions of Prime Numbers and each one may be correct in its own way. However, here is the definition given in NCERT books is this – “The numbers other than 1 whose only factors are 1 and the number itself are called Prime Numbers“. A natural number greater than 1 that is not prime is called a composite number. We can check whether a number is prime or composite using the prime factorisation. Read this article to learn how to check whether a number is prime or composite and get the list of prime numbers from 1 to 1000.

Going by the easiest and most effective definition, prime numbers can be defined as the “Numbers which are only divisible by 1 and the number itself”. For instance, 5 is prime because it has only 2 factors, 1 × 5 or 5 × 1, including 5 itself. However, 4 is composite because it is a product of 1 × 4 or 4 × 1 and 2 × 2. To understand this better, take a look at the table below:

 Numbers Factors Number Of Factors 1 2 3 4 5 6 7 8 9 10 11 12 1 1, 2 1, 2 1, 2, 4 1, 5 1, 2, 3, 6 1, 7 1, 2, 4, 8 1, 3, 9 1, 2, 5, 10 1, 11 1, 2, 3, 4, 6, 12 1 2 2 3 2 4 2 4 3 4 2 6

In the above table, 2,3,5,7 and 11 are primes because they have only 2 factors – 1 and the number itself.

So from the above table, we can devise another definition of Prime Numbers – “Numbers having exactly 2 factors are known as Prime Numbers“.

Fun Exercise For You: Try to find the list of Prime Numbers between 1 to 50. You can also play it as a competition with your friends and once done you can check the answers from the table in the next section.

We have provided the list of primes between 1 to 1000 below:

 Prime Number Between 1 To 500 Prime Numbers Between 500 To 1000 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, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499. 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997.

Quick Tip: 1 is not a prime number as it has only 1 factor.

Some properties through which you can decide whether a number is prime or not are listed below:

Often students have difficulty in finding the types of prime numbers. So, we have tabulated the types below:

 Even Prime Numbers Odd Prime Numbers Coprime Numbers Twin Prime Numbers Prime Numbers divisible by 2. Prime Numbers not divisible by 2. Numbers having only 1 as their common factor or HCF = 1. Prime Numbers with a gap of 2 between them. Eg: 2. Eg: 3, 5, 7, 9, 11, etc. Eg: 18 and 35. Eg: 3 & 5 or 821 & 823.

Eratosthenes was a Greek Mathematician from the 3rd century BC who devised a method to find the Prime nos. using the below chart.

Now that you are well aware of the steps to know Prime nos. you can easily differentiate them from composite numbers.

 Composite Numbers Prime Numbers It has more than 2 factors. It has only 2 factors. These numbers are divisible by all their factors. These are divisible by themselves and 1 only. Eg: 6, 12, 15, 50, 124, 188, etc. Eg: 5, 11, 61, 157, 457, etc.

So, now you have all the information on Prime Numbers, their properties, list of prime numbers from 1 to 1000, the method to find prime numbers. Let us provide you with some questions along with solutions. Since this topic belongs to CBSE NCERT Solutions For Class 6 Maths Chapter 3 Playing With Numbers, you can click the link to download the solutions for the exercise questions as well.

 Example 1: Is 15 a Prime Number? Solution 1: No, 15 is not a Prime Number because it is divisible by 1, 3, 5, and 15.
 Example 2: Is 19 Prime or not? Solution 2: Yes, since 19 has only two factors i.e. 1 and 19, it is prime.
 Example 3: Write 3 pairs of Prime Numbers less than 20 whose sum is divisible by 5? Solution 3: 3+2 = 5, 3+7 = 10, 2+13 = 15.
 Example 4: Find the Prime Numbers from the following: 34, 27, 29, 41, 67, 83 Solution 4: 34 – Not prime. 27 – Divisible by 3, 9; hence, not prime. 29, 41, 67, 83 – All are prime (divisible by 1 and themselves only).

Here are some questions that students look for:

 Que. What are the Prime Numbers from 1 to 1000? Ans. We have listed all the Prime Nos. in this article – 2 being the smallest and 997 being the largest between 1 to 1000.
 Que. Which is the only even Prime Number/ Which is the smallest prime number? Ans. 2.
 Que. What are the Prime Numbers between 1 to 200? Ans. The Prime Nos between 1 to 200 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, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199.
 Que. How many factors does a Prime Number have? Ans. A Prime No. has only 2 factors.

That was all the information on Prime Numbers. We hope the information provided here helps you. However, if you have any questions, feel free to use the comments section below to reach out to us and we will get back to you at the earliest.

Practice Prime Numbers Questions with Hints & Solutions