from itertools import count

LIMIT = 10**9


def f(n: int) -> int:
    ds = sorted([int(c) for c in str(n)])
    res = 0
    for d in ds:
        res = 10*res + d

    return res


d = {}
for i in count(1):
    x = i*i
    if x > LIMIT: break

    y = f(x)
    if y not in d:
        d[y] = x


def solve():
    N = int(input())
    x = f(N)
    if x in d:
        return d[x]

    return -1



T = int(input())
for _ in range(T):
    res = solve()
    print(res)