"Google **tifies you via email and/or text message when your password is changed, and when we detect a suspicious attempt to sign in to your account. If you receive a **tification about a password change you didn't make, or an attempt to sign in to your account that wasn't you, these email and text message **tifications will provide details on next steps to help you secure your account," informs Google.
This feature should be available under the "security" tab of the Account Settings page, but I don't see it. Maybe it's enabled in your accounts.