There are 6.
Two carbons have to be identical in all ways in terms of everything to which they are attached to or else the environments are different.
I've drawn it out for you:
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Carbon 1 is directly attached to a cyclopropane unit, while carbon 6 is directly attached to a CH2 group.
These are different environments.
I don't know whether this is beyond what you've learned so far, but it's my opinion that "white" lies shouldn't be told in science education, as they just lead students to be confused later on.
Worth noting this isn't the only possible answer