import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.math.BigDecimal; import java.math.RoundingMode; import java.util.*; public class Main { static final long MOD=1000000007; static final long MOD1=998244353; static int ans=0; public static void main(String[] args){ PrintWriter out = new PrintWriter(System.out); InputReader sc=new InputReader(System.in); int T = sc.nextInt(); long[] prime = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31}; for (int i = 0; i < T; i++) { long X = sc.nextLong(); out.println(f(X, prime)); } out.flush(); } static long f(long X,long[] prime) { long a = 1l; long X_ = X; for (int i = 0; i < prime.length; i++) { long a_=0; long p = prime[i]; while (X_%p==0) { X_/=p; a_++; } a *= (a_ + 1l); } for (long i = 2; i <= 31; i++) { long b = 1; long cX = X*i; for (int j = 0; j < prime.length; j++) { long p = prime[j]; long b_ = 0; while (cX%p==0) { cX/=p; b_++; } b *= (b_ + 1l); } if (b%a==0&&b/a==2) { return X*i; } } return -1; }; static class InputReader { private InputStream in; private byte[] buffer = new byte[1024]; private int curbuf; private int lenbuf; public InputReader(InputStream in) { this.in = in; this.curbuf = this.lenbuf = 0; } public boolean hasNextByte() { if (curbuf >= lenbuf) { curbuf = 0; try { lenbuf = in.read(buffer); } catch (IOException e) { throw new InputMismatchException(); } if (lenbuf <= 0) return false; } return true; } private int readByte() { if (hasNextByte()) return buffer[curbuf++]; else return -1; } private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); } private void skip() { while (hasNextByte() && isSpaceChar(buffer[curbuf])) curbuf++; } public boolean hasNext() { skip(); return hasNextByte(); } public String next() { if (!hasNext()) throw new NoSuchElementException(); StringBuilder sb = new StringBuilder(); int b = readByte(); while (!isSpaceChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public int nextInt() { if (!hasNext()) throw new NoSuchElementException(); int c = readByte(); while (isSpaceChar(c)) c = readByte(); boolean minus = false; if (c == '-') { minus = true; c = readByte(); } int res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res = res * 10 + c - '0'; c = readByte(); } while (!isSpaceChar(c)); return (minus) ? -res : res; } public long nextLong() { if (!hasNext()) throw new NoSuchElementException(); int c = readByte(); while (isSpaceChar(c)) c = readByte(); boolean minus = false; if (c == '-') { minus = true; c = readByte(); } long res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res = res * 10 + c - '0'; c = readByte(); } while (!isSpaceChar(c)); return (minus) ? -res : res; } public double nextDouble() { return Double.parseDouble(next()); } public int[] nextIntArray(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) a[i] = nextInt(); return a; } public double[] nextDoubleArray(int n) { double[] a = new double[n]; for (int i = 0; i < n; i++) a[i] = nextDouble(); return a; } public long[] nextLongArray(int n) { long[] a = new long[n]; for (int i = 0; i < n; i++) a[i] = nextLong(); return a; } public char[][] nextCharMap(int n, int m) { char[][] map = new char[n][m]; for (int i = 0; i < n; i++) map[i] = next().toCharArray(); return map; } } }