C = {i:set() for i in range(1,11)}
D = {}
for i in range(1,10**9+1):
    j = i*i
    if j>10**9:break
    j = sorted(list(str(j)))
    n = j.count("0")
    j = j[n:]
    flag = False
    for k in range(n+1):
        if tuple(j) in C[len(j)]:
            flag = True
            break
        j = ["0"]+j
    if not flag:
        j = j[1:]
        C[len(j)].add(tuple(j))
        D[tuple(j)] = i*i
T = int(input())
for _ in range(T):
    N = str(int(input()))
    n = N.count("0")
    N = sorted(list(N))
    N = N[n:]
    ans = -1
    for i in range(n+1):
        if tuple(N) in C[len(N)]:
            ans = D[tuple(N)]
            break
        N = ["0"]+N
    print(ans)