Segmentation fault using array of promises

I've written multithreading program, using promises and futures to check whether given number is prime. The correctness or efficiency of this program is not a point, but fact of the segmentation error which occurs in every execution - I had similar problem with more complex program, so I've written this simple one to understand it, and the error is still here. Maybe I don't understand something about concurrency, or promises/futures, but I think that everything is done here in proper way... Can anybody explain why it's not working? It would be very helpful :)

Here's the code:

#include <future>
#include <thread>
#include <iostream>
#include <initializer_list>
#include <vector>
#include <cassert>


namespace {
const int THREADS_NUMBER = 8;

void f(int n, std::vector<int>& divisiors, std::promise<bool>& isPossiblePrime) {
    bool isPrimeCandidate = true;
    for (auto i : divisiors)
        if (n % i == 0) {
            isPrimeCandidate = false;
            break;
        }
    isPossiblePrime.set_value(isPrimeCandidate);
}


}

int main() {
    int n;
    std::cin >> n;
    assert(n > 2);
    std::promise<bool> promises[THREADS_NUMBER];
    std::future<bool> futures[THREADS_NUMBER];
    for (int i = 0; i < n; i++)
        futures[i] = promises[i].get_future();
    std::thread threads[THREADS_NUMBER];

    std::vector<int> divisiors[THREADS_NUMBER];
    for (int i = 2; i < n; i++)
        divisiors[i % THREADS_NUMBER].push_back(i);

    for (int i = 0; i < THREADS_NUMBER; i++) 
        threads[i] = std::thread{ [&]() { f(n, divisiors[i], promises[i]); }};

    bool isPrime = true;
    for(auto & f : futures) {
        bool out = f.get();
        isPrime = out && isPrime;
    }

    for (auto& t : threads)
        t.join();

    if(isPrime) std::cout << "PRIME" << std::endl;
    else std::cout << "NOT PRIME" << std::endl;

}

I compile with g++ -std=c++11 -Wall -lpthread on Linux.