#include <iostream>
#include <algorithm>
using namespace std;

long long md = 1000000007;

long long fp(long long n, long long k, long long m)
{
    long long s = 1;
    while (k) {
        if (k & 1LL) s = (s * n) % m;
        n = (n * n) % m; k /= 2;
    }
    return s;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    long long a, b, c, k; cin >> a >> b >> c >> k;
    a = (a * b) % md; a = (a * c) % md;
    cout << fp(a, fp(2, k, md - 1), md) << '\n';
    return 0;
}