C program to print the prime numbers in the range 2 to given number

Following is a C program which prints the prime numbers in the range 2 to the given number by the user:

/*C program to print prime numbers from 2 to given number*/
main()
{
    int number,i,j,flag;
    clrscr();
    printf("Enter a number:");
    scanf("%d",&number);
    if(number<2)
    {
        printf("Invalid number!");
    }
    else
    {
        printf("Prime numbers in the range 2 to %d are:\n",number);
        for(i=2;i<=number;i++)
        {
            flag = 0;
            for(j=2;j<=i-1;j++)
            {
                if(i%j==0)
                {
                    flag = 1;
                }
            }
            if(flag==0)
            {
                printf("%d ",i);
            }
        }
    }
    getch();
}

Sample input and output:
Enter a number:100
Prime numbers in the range 2 to 100 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