How are social security numbers determined?

Question

How are social security numbers determined?

Answer 1

Under the current system, the first three digits of the Social Security number indicate the state of residence of the holder at the time when the card was issued.  The other digits have no significance.

However, before 1973, the first three digits were assigned by local SS offices instead.  The system was changed because people could easily get another card just by applying at a different office.