What output will be produced by the following code?

```
public class Demo {
public static void main(String[] args) {
System.out.println("The output is:");
foo(23);
System.out.println();
}
public static void foo(int number) {
if (number > 0) {
foo(number / 2);
System.out.print(number % 2);
}
}
}
```

The output is:
10111

This code is in Demo1.java.