package main

import . "fmt"
import . "slices"

func main() {
	var t int
	Scan(&t)
	m := map[string]int{}
	for i := 1; i * i <= 1e9; i++ {
		ii := i*i
		s := []byte(Sprint(ii))
		Sort(s)
		for len(s) <= 9 {
			if _, ok :=m[string(s)]; !ok {
				m[string(s)] = ii
			}
			s = append([]byte{'0'}, s...)
		}
	}
	for ; t > 0 ; t-- {
		var n string
		Scan(&n)
		b := []byte(n)
		Sort(b)
		if ans, ok := m[string(b)]; ok {
			Println(ans)
		} else {
			Println(-1)
		}
	}
}