If you want to work in Armenia or have access to social services, you must have what is known as a social card.
After you receive your registration, go to your local police station and approach a window and tell them you are looking for a social service card. They will ask you if you have your registration and you will present to them your stamped residency card. They will then prepare a sheet with a social number on it and tell you when to come back for it. Once ready, the sheet will contain your social services number that you would give to an employer.
Make copies and scan or take a picture of the sheet so that you have a record of it. Also, keep it somewhere safe and easily accessible for when you need it.
This section is cited from RepatArmenia Foundation.