#include <bits/stdc++.h>

using i64 = long long;

std::vector<int> minp, primes;

void sieve(int n) {
    minp.assign(n + 1, 0);
    primes.clear();
    
    for (int i = 2; i <= n; i++) {
        if (minp[i] == 0) {
            minp[i] = i;
            primes.push_back(i);
        }
        
        for (auto p : primes) {
            if (i * p > n) {
                break;
            }
            minp[i * p] = p;
            if (p == minp[i]) {
                break;
            }
        }
    }
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    int k;
    std::cin >> k;
    
    std::vector<int> p(k), e(k);
    for (int i = 0; i < k; i++) {
        std::cin >> p[i] >> e[i];
    }
    
    int P = p[k - 1];
    sieve(P);
    
    std::vector<int> pw(P + 1);
    int cnt = 0;
    for (int i = 0; i < k; i++) {
        pw[p[i]] = e[i];
    }
    for (int i = 1; i <= P; i++) {
        cnt += (pw[i] != 0);
    }
    
    int r = 0;
    while (cnt != 0 && r < P) {
        r++;
        
        for (int x = P - r + 1; x > 1; x /= minp[x]) {
            int p = minp[x];
            cnt -= (pw[p] != 0);
            pw[p]--;
            cnt += (pw[p] != 0);
        }
        
        for (int x = r; x > 1; x /= minp[x]) {
            int p = minp[x];
            cnt -= (pw[p] != 0);
            pw[p]++;
            cnt += (pw[p] != 0);
        }
    }
    
    if (cnt != 0) {
        std::cout << -1 << " " << -1 << "\n";
        return 0;
    }
    
    std::cout << P << " " << r << "\n";
    
    return 0;
}