If I declare "Const foo as Integer = 123", does that allocate storage?

Or does that create a compile-time constant that replaces "foo" wherever it
is used in executable statements?

If the latter, is "Const foo as Integer = 123*456" and "x = foo" more
efficient than "x = 123*456"? In particular, does the compiler treat "x =
foo" as "x = 56088"?