#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <math.h>
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <numeric>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <bitset>

typedef unsigned long long ULLONG;
typedef long long LLONG;
static const LLONG MOD_NUM = 1000000007; //998244353;

template<class _T> static void get(_T& a) {
	std::cin >> a;
}
template<class _T> static void get(_T& a, _T& b) {
	std::cin >> a >> b;
}
template<class _T> static void get(_T& a, _T& b, _T& c) {
	std::cin >> a >> b >> c;
}
template <class _T> static _T tp_abs(_T a) {
	if (a < (_T)0) {
		a *= (_T)-1;
	}
	return a;
}

static void exec();

int main()
{
	exec();
	fflush(stdout);
	return 0;
}
template <class _T> static _T tp_modfact(_T n, _T k, _T mod = (_T)1) {
	_T count = 0;
	_T ans = 1;

	while (count < k) {
		ans = ans * (n - count) % mod;
		count++;
	}
	return ans;
}
template <class _T> void tp_getPrimes(_T targ, std::map<_T, _T>& primes)
{
	_T target = targ;
	_T i = 2;
	while ((i * i) <= target) {
		if ((target % i) == 0) {
			target /= i;
			primes[i]++;
		}
		else {
			i++;
		}
	}
	if (target > 1) {
		primes[target]++;
	}
}

static void exec()
{
	int T;
	get(T);

	LLONG A, P;
	std::map<LLONG, LLONG> prime;
	while (T--) {
		scanf("%lld %lld", &A, &P);
		prime.clear();
		tp_getPrimes<LLONG>(P, prime);

		LLONG ans = -1;
		if (prime.size() == 1 && prime.begin()->second == 1) {
			ans = 1;
		}
		printf("%lld\n", ans);
	}
}