Why are these == but not `equals()`?

I'm a bit confused about the way Java treats == and equals() when it comes to int, Integer and other types of numbers. For example:

Integer X = 9000;
int x = 9000;
Short Y = 9000;
short y = 9000;
List<Boolean> results = new ArrayList<Boolean>();
// results.add(X == Y); DOES NOT COMPILE        1)
results.add(Y == 9000);                      // 2)
results.add(X == y);                         // 3)
results.add(X.equals(x));                    // 4)
results.add(X.equals(Y));                    // 5)
results.add(X.equals(y));                    // 6)
System.out.println(results);

outputs (maybe you should make your guess first):

[true, true, true, false, false]

1. That X == Y does not compile is to be expected, being different objects.
2. I'm a little surprised that Y == 9 is true, given that 9 is by default an int, and given that 1) didn't even compile. Note that you can't put an int into a method expecting a Short, yet here they are equal.
3. This is surprising for the same reason as two, but it seems worse.
4. Not surprising, as x is autoboxed to and Integer.
5. Not surprising, as objects in different classes should not be equal().
6. What?? X == y is true but X.equals(y) is false? Shouldn't == always be stricter than equals()?

I'd appreciate it if anyone can help me make sense of this. For what reason do == and equals() behave this way?

Edit: I have changed 9 to 9000 to show that this behavior is not related to the any unusual ways that the integers from -128 to 127 behave.

2^nd Edit: OK, if you think you understand this stuff, y