Prime Numbers

A composite number.

120 has the prime factorization 8 x 3 x 5

Those are known as square numbers, like 4 and 9.

The number 12 is not prime. It can be divided by 2 and 6 as well as itself and 1
No, 12 is a composite since you can divide it by 2.

1 x 3 x 72

The factors of -30 are 1, 2, 3, 5, 6, 10, 15, 30 and their negatives.

The prime factors are 2, 3, 5

Yes.

(9-(2*3))8

111 of them.

2 3 5 7 11 13 17 19 23 29

1, 2 and 4.

Well, the presence and abundance of predators, of course.

230 = 2 x 5 x 23

If you include 2 and 11, the prime numbers are 2, 3, 5, 7, and 11.

2 is prime.

A 28 digit number. Non prime. Incorrectly written and of no other significance.

When referring to positive integers, prime means having only two factors and composite means having more than two.

import java.io.*;

class PrimeFactors

{

private boolean prime(int a)

{

boolean b=true;

for(int i=2;i<=(a/2);i++)

{

if(a%i==0)

b=false;

}

return b;

}

protected static void main()throws IOException

{

BufferedReader in=new BufferedReader(new InputStreamReader(System.in));

System.out.print("Enter the Number: ");

int a=Integer.parseInt(in.readLine());

PrimeFactors o=new PrimeFactors();

System.out.println("Prime Factors of "+a+" are::");

for(int i=1;i<=(a/2);i++)

{

if(a%i==0)

{

boolean b=o.prime(i);

if(b==true)

System.out.print(i+" ");

}

}

}}

Check the McGraw-Hill website, www.mcgraw-hill.com. They usually have pretty good study guides.

The square root from 1987 is less than 45, so we should check the division by the numbers less than 45.

1987 is not divided by 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43 - hence it is a prime number/

233357 is the prime factorization of the number 2x3x3x3x5x7=1890

270 = 2 × 33 × 5

If done correctly, yes.

'''They called composite numbers.'''

'''Composite numbers are when they have more than two factors.'''

'''A prime number is when it only has 2 factors no more or less.'''

'''EX : 20'''

'''Factors Of 20 : 1, 20, 2, 10, 4, 5.'''