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Prime Numbers

Prime numbers are a special category of natural numbers or positive integers which are exactly divisible by 1 and the number itself. So, a prime number has exactly two divisors. Prime number is a number which is greater than 1 and which can be efficiently divided by 1 and by itself not by any other number. It is also a whole number.
An Integer P > 1 is called a prime number when its only divisors are ± 1 and ± P. Any number m > 1 which is not a prime is called a composite.

Theorem: Every compositely number could be factored into prime factors and each of these is unique in nature.Simple properties of primes:

(a) A prime 'p' is either relatively prime to a number 'n' or divided it.
(b) A product is divisible by a prime 'p' only when 'p' divides one of the factors.
(c) Every n > 1 is divisible by some prime.

 

What is a Prime Number?

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What are Prime Numbers? Prime numbers are natural numbers which have only two divisors which are 1 and the number itself.

These numbers comes under the study of elementary math. Learn to distinguish all the prime numbers from the composite numbers.

Are all Prime Numbers Odd?


Yes all prime numbers are odd, but only even prime number is 2. Since every other even number can be divide by a 2.

Prime Number Definition

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Prime numbers are a special category of natural numbers or positive integers which are exactly divisible by 1 and the number itself. So, a prime number has exactly two divisors.
Largest Prime Number

m39 = 213,466,917-1 is the largest prime number.

Smallest Prime Number

As we know, 2 is the smallest prime number.

List of Prime Numbers

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Till now we have explained the concept of prime numbers and given below is list of prime numbers for your better knowledge.

The list from 1 to 200 are as follows:

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

Is 1 a Prime Number?

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According to the prime number definition, we can say that 1 is not a prime number. The definition says that a prime number should have exactly two divisors. But 1 has only one divisor. So, 1 is not a prime number.

Is 2 a Prime Number


Yes, 2 is a prime number because it is divisible by itself and 1.

How to Find Prime Numbers

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Let's identify whether the following numbers are prime or not

The number 2 is exactly divisible by 2 and 1

The number 3 is exactly divisible by 3 and 1

The number 4 is exactly divisible by 4, 2 and 1

The number 5 is exactly divisible by 5 and 1

The number 6 is exactly divisible by 6, 3, 2 and 1

The number 7 is exactly divisible by 7 and 1

The number 8 is exactly divisible by 8, 4, 2 and 1

The number 9 is exactly divisible by 9,3 and 1

The number 10 is exactly divisible by 10, 5, 2 and 1

The numbers 4, 6, 8, 9, 10 are not prime numbers since it has more than 2 factors.

The numbers 2, 3, 5, 7 are prime numbers since it has exactly two factors, 1 and the number itself. You can learn more about

prime numbers online with the help of out tutors.


Twin Prime Numbers

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  • 1 is neither prime nor composite.
  • 2 is the least even prime number.
  • 3 is the least odd prime number.
  • If there is only one composite number between two primes,the primes said to between prime numbers.
  • For example: 5 and 7 In between 5 and 7 the only one composite number is 6.
  • If two or more than two numbers have no common divisor other than 1 ,then they are called as relatively prime or co-prime numbers.

Prime Number Theorem

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Prime Number Theorem precisely gives us the value to which the density of prime numbers less that a given number approaches as the numbers grow larger and larger i.e. tend to infinity. There are many proofs easily accessible on the internet or otherwise. Hence only its statement is being given here.

Statement of Prime Number Theorem:

Let P(x) be the number of prime numbers less than x, where x > 1 and x is a real number. Then the prime number theorem states

$\lim_{x \to \infty }$ $\frac{P(x)}{\frac{(x)}{(log x)}}$ =1.

This asymptotic formula precisely gives the value to which prime number density approaches as the numbers grow larger and larger. It has been termed as one of the most beautiful and important theorems in the history of mathematics and number theory.
More topics in  Prime Numbers
Prime Numbers up to 100 Properties of Prime Numbers
Relatively Prime Numbers
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