#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;
using ll = long long;

#include<atcoder/modint>
using mint = atcoder::modint1000000007;

ll mpow(ll n,ll k,ll mod){
    ll a = 1;
    while(k){
        if(k&1) a = (a*n) % mod;
        n = (n*n) % mod;
        k >>= 1;
    }
    return a;
}
int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    ll a,b,c;
    cin>>a>>b>>c;
    ll k;
    cin>>k;
    ll use = mpow(2,k,1000000006);
    mint ans = mint(a) * mint(b) * mint(c);
    ans = ans.pow(use);
    cout<<ans.val()<<endl;
}