public class NumberUtils {

    public static boolean isPositivePrime(int number) {
        if(number>1) {
            for(int i = 2; i < number; i++) {
                if(number % i == 0)
                    return false;
            }
        return true;
        }
        return false;
    }

    public static int factorial(int number) {
        int sum = 1;
        if(number > 0) {
            for(int i = 1; i < number; i++) {
                sum += sum * i;
            }
            return sum;
        }else {
            return -1;
        }

    }

    public static boolean isPerfect(int number) {
        int sum = 0;
        if(number > 1)
        for(int i = 1; i < number; i++) {
            if(number % i == 0)
                sum += i;
        }

        if(sum == number && sum > 0)
            return true;

    return false;
}


    public static String getPerfects(int number) {
        String primes = "";
        for(int i = 0; i <= number; i ++) {
            if(isPerfect(i))
                primes += i+",";
        }
        return primes;

    }

    public static boolean isSumDigits(int number, int someSum) {
        int sum = 0;
        if(number > 0) {
            while(number != 0) {
                sum +=  number % 10;
                number /= 10;
            }

        }
        if(someSum == sum)
            return true;

                    return false;
    }

    public static boolean isAscending(int number) {
        int temp = number % 10;
        while(number != 0) {
            if((number / 10) % 10 >= temp) {
                return false;
            }else {
                number /= 10;
                temp = number % 10;

            }
        }
    return true;
    }

    public static boolean areUniqueDigits(int number) {
    int comparedNumbers = number / 10;
    int lastDigit = number % 10;

    while(number != 0) {
        while(comparedNumbers != 0) {
            if(lastDigit == comparedNumbers % 10)
                return false;
            comparedNumbers /= 10;
        }
        number /= 10;
        comparedNumbers = number / 10;
        lastDigit = number % 10;
    }

    return true;
    }

    public static boolean areDisjoint(int number1, int number2) {

        int longerClone = number1;
        int lastDigit = number2 % 10;
        while(number2 != 0) {
            while(number1 != 0) {
                if(lastDigit == number1 % 10)
                return false;
                number1 /= 10;
            }
            number2 /= 10;
            lastDigit = number2 % 10;
            number1 = longerClone / 10;
            longerClone /= 10;
        }
        return true;
    }

    public static void printNumberTriangle(int n) {
        for(int i = n; i > 0; i--) {
            for(int j = 1; j < i; j++) {
                System.out.print("*");
            }
            for(int a = n-i; a >= 0; a--) {

                System.out.print(a+1);
            }
        System.out.println();
        }

    }

}