program z558;
uses crt;
var p,d:integer;
BEGIN
clrscr;
writeln('vvedite p');
readln(p);
d:=1;
repeat
Inc(d);
until (d>p div 2) or (p mod d=0);
if d

then writeln('chislo 2^', p,' -1 prostoe')
else writeln('chislo 2^', p,' -1 ne prostoe');
readln;
END.