program zzz;
var n,l,i,j,k : longint;
    q : real;
    s : string;
    a : array [1..100000] of byte;
begin
   read(n);
   k := 0;
   if n = 0 then begin
      write(0);
      halt;
   end;
   while true do begin
      for i := 9 downto 2 do begin
         if n mod i = 0 then begin
            k := k+1;
            a[k] := i;
            n := n div i;
            break;
         end;
      end;
      if (n < 10) then begin
         if n > 1 then begin
            k := k+1;
            a[k] := n;
         end;
         break;
      end;
      if i = 2 then begin
         write(-1);
         halt;
      end;
   end;
   for i := 1 to k-1 do begin
      for j:= i+1 to k do begin
         if a[i]>a[j] then begin
            l := a[i];
            a[i] := a[j];
            a[j] := l;
         end;
      end;
   end;
   if k = 0 then write(1);
   for i := 1 to k do begin
      write(a[i]);
   end;
end.

> program zzz;
> var n,l,i,j,k : longint;
>     q : real;
>     s : string;
>     a : array [1..100000] of byte;
> begin
>    read(n);
>    k := 0;
>    if n = 0 then begin
>       write(0);
>       halt;
>    end;
>    while true do begin
>       for i := 9 downto 2 do begin
>          if n mod i = 0 then begin
>             k := k+1;
>             a[k] := i;
>             n := n div i;
>             break;
>          end;
>       end;
>       if (n < 10) then begin
>          if n > 1 then begin
>             k := k+1;
>             a[k] := n;
>          end;
>          break;
>       end;
>       if i = 2 then begin
>          write(-1);
>          halt;
>       end;
>    end;
>    for i := 1 to k-1 do begin
>       for j:= i+1 to k do begin
>          if a[i]>a[j] then begin
>             l := a[i];
>             a[i] := a[j];
>             a[j] := l;
>          end;
>       end;
>    end;
>    if k = 0 then write(1);
>    for i := 1 to k do begin
>       write(a[i]);
>    end;
> end.

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