#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>
#include <complex>
#include <cassert>

using namespace std;
using ll = long long;

const ll modc = 1e9+7;

long long mod_exp(long long b, long long e, long long m){
    if (e > 0 && b == 0) return 0;
    long long ans = 1;
    b %= m;

    while (e > 0){
        if ((e & 1LL)) ans = (ans * b) % m;
        e = e >> 1LL;
        b = (b*b) % m;
    }

    return ans;
}

int main(){

    ll A, B, C, D, K;
    cin >> A >> B >> C >> K;
    D = ((A*B) % modc * C) % modc;
    K = mod_exp(2, K, modc-1);

    cout << mod_exp(D, K, modc) << endl;

    return 0;
}