The nucleolus doesn't have a distinct outer membrane or boundary like other cellular organelles. It's essentially a dense region within the nucleus, formed by the accumulation of ribosomal RNA (rRNA) and proteins. So, it's not accurate to talk about an "outside" of the nucleolus in the same way you would for something like a cell membrane.

However, you can refer to the nucleoplasm as being outside of the nucleolus. This is the gel-like substance that fills the nucleus and surrounds the nucleolus.