import java.util.*;

public class Main {
    static final int MOD = 1000000007;
	public static void main (String[] args) {
		Scanner sc = new Scanner(System.in);
		long b = sc.nextLong() % MOD;
		long c = sc.nextLong() % MOD;
		long d = sc.nextLong();
		System.out.println(sum(b * c % MOD, c, d));
   }
   
   static long pow(long x, long y) {
       long ret = 1;
       x %= MOD;
       while (y > 0) {
           if (y % 2 == 1) {
               ret *= x;
               ret %= MOD;
           }
           x *= x;
           x %= MOD;
           y /= 2;
       }
       return ret;
   }
   
   static long sum(long a, long r, long n) {
       if (n == 1) {
           return a % MOD;
       }
       long x = sum(a, r, n / 2);
       long ret = (x + pow(r, n / 2) * x) % MOD;
       if (n % 2 == 1) {
           ret *= r;
           ret += a;
           ret %= MOD;
       }
       return ret;
   }
}