Do you compare your memories with others or others'?

You (plural) have different memories. Suppose you are all students in my class. Now I want to ask you to compare your memories by talking to students in another class and hearing about their memories. So should I say:

Compare your memories with others?

or

Compare your memories with others'?

The second makes more sense because you are not comparing your memories to people but to THEIR memories, but something about the sentence looks weird, so I thought to ask here.

It depends what you mean. The difference is subtle, but there is a difference.

Compare your memories with others.

Compare your memories with other memories. Obviously, the other memories must be other people's memories, but others here is referring to memories, not people. That is, others corresponds to memories in your sentence.

Compare your memories with others'.

Compare your memories with those of other people. Here, others' matches your in your sentence.

I guess that in most cases, the sentence is directing you to the "those of other people" meaning, in which case an apostrophe is preferable.