Bitwise NOT Operation

I was looking into some of the System stored procedures like sp_denylogin, sp_grantLogin etc. I found bit wise operations like

update master.dbo.sysxlogins set xstatus = (xstatus & ~1) | 2, xdate2 = getdate()
where name = @loginame and srvid IS NULL

How does the bitwise NOT(~) works with different datatypes like INT, SMALLINT and TINYINT?

Look at the following sample code and result. I just wanted to understand how it works with int and smallint


declare @a int
declare @b smallint
declare @c tinyint

select @a = 1, @b = 1, @c = 1

select @a=~@a, @b= ~@b, @c= ~@c

select @a, @b, @c

Result
~~~~~
-2-2254

Thanks in advance
Gnana