It is not visible by default. Only you see it when looking at your own profile, but not others.
In any case, go to your profile, then to account related settings, and check that “Hide email address from public?” is ticked (see
account related settings , where 2709791 is your ID, and the configuration screen this link takes you to is only accesible by you).
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No. We are both logged-in, and your email is not visible (it states 'hidden')