import sys def input(): return sys.stdin.readline().strip() def list2d(a, b, c): return [[c] * b for i in range(a)] def list3d(a, b, c, d): return [[[d] * c for k in range(b)] for i in range(a)] def list4d(a, b, c, d, e): return [[[[e] * d for k in range(c)] for k in range(b)] for i in range(a)] def ceil(x, y=1): return int(-(-x // y)) def INT(): return int(input()) def MAP(): return map(int, input().split()) def LIST(N=None): return list(MAP()) if N is None else [INT() for i in range(N)] def Yes(): print('Yes') def No(): print('No') def YES(): print('YES') def NO(): print('NO') sys.setrecursionlimit(10**9) INF = 10**19 MOD = 10**9 + 7 EPS = 10**-10 def eratosthenes_sieve(n): """ 素数列挙(エラトステネスの篩) """ table = [0] * (n+1) prime_list = [] for i in range(2, n+1): if table[i] == 0: prime_list.append(i) for j in range(i+i, n+1, i): table[j] = 1 return prime_list primes = set(eratosthenes_sieve(5000000)) for _ in range(INT()): a, p = MAP() if p in primes: ans = pow(a, p-1, p) print(ans) else: print(-1)