Which objects are atomic in Mathematica?

I am looking for a full list of atomic objects in Mathematica (for which AtomQ yields True).

I know about

Symbol
String
Integer
Real
Rational
Complex

SparseArray
BooleanFunction
Graph

Are there开发者_StackOverflow any others?

ref: http://reference.wolfram.com/mathematica/tutorial/BasicObjects.html

EDIT: Continually adding new symbols from answers to list above.

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It appears your list needs one more object to be complete:

In[520]:= f = BooleanFunction[30, 3];

In[521]:= AtomQ[f]

Out[521]= True

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Looks like we have another one:

obj = Graphics`Mesh`Delaunay @ RandomReal[1, {10, 2}]

AtomQ[obj]

"MeshObject[1]"[2, {10, 21, 12}]

True