Anyone who has a social security number has an SS-5 form, the "application for Social Security and Tax Account Number" appears on the right.
I don't often get these. They are $27 from the Social Security Administration and are open to the public for anyone who is deceased. They are helpful when other records are not available or other records are confusing. The one on the right is for my wife's grandmother. It is one of the few I have...because in her case records were inconsistent.
Keep in mind that for more individuals these forms were filled out by the applicant themselves. That is usually not the case with death certificates and why in some situations these records provide information that is at odds with the death record.
More about SS5 forms can be located on our site at http://www.rootdig.com/ss5/
Michael