Most Americans are given a first and last name when they're born, but aggregate data on full names is not widely distributed by any federal government agency. Instead, data on first and last names is compiled and released separately by two different agencies. The Social Security Administration (SSA) releases an annual list of first names given to babies born in the United States, while the Census bureau provides a list of last names of individuals living in the U.S. once every decade or so.

But there are some sources of information on full names. One is the Social Security Death Master File (DMF). The DMF is widely used as a death verification tool, though a fraction of a percent of the individuals are added erroneously while still alive (and not all deaths are recorded). The most recent publicly available full version is from 2013 and contains over 87 million entries. Eighty percent of the entries were born 1930 or earlier, so the group skews older. While the DMF doesn’t provide an exhaustive list, there are still a lot of very unusual full names among them. Here are seven fun facts about American names from the DMF.

1. NUMBER OF PEOPLE WITH AN IDENTICAL FIRST AND LAST NAME: 4746

There were 1560 different first and last name combinations. Thomas Thomas is by far the most frequently occurring, followed by James James. Alexander Alexander and Santiago Santiago make a good showing. The most frequently occurring female name is Rose Rose at number three. The rest of the top names are predominantly male. Of the top 25, only four are names that are overwhelmingly female: Rose Rose, Ruth Ruth, Grace Grace, and Rosa Rosa.

2. NUMBER OF PEOPLE WHOSE LAST NAME STARTS WITH THEIR FIRST NAME: 45,379

Excluding people with identical first and last names, there are 4344 different names where the last name starts with the first name. More than a quarter of the total occurrences are for John Johnson, followed by William Williams. Similar to Johnson and Williams, almost all the last names are patronymic. Their original meaning was to denote someone is “son of [insert father’s name].” The top 25 include patronymic last names that are English (ending in son, like Robert Robertson), Welsh (often ending in s, like Edward Edwards), Danish (ending in sen, like Jens Jensen), and Spanish (ending in ez, like Martin Martinez). Given that by definition, a patronym includes the name of the male parent, it’s unsurprising that boys’ first names dominate the top of the list. The top female name is Eva Evans at number 19, with only two more in the top 25, neither of which are patronymic (Rose Rosen and Rose Rosenberg).

3. NUMBER OF PEOPLE WITH A LAST NAME THAT ENDS WITH THEIR FIRST NAME: 5840

Patronymic last names are not always signified by their endings. In some cases, it’s the beginning of the last name that gives it away. Such is the case with Gaelic (last names starting with Mc or Mac or O’ in Ireland for "grandson of") and Norman (start with Fitz). From a total of 2201 different first and last names where the last name ends with the first, the top four names are all patronymic. They are, in order: Donald MacDonald, Donald McDonald, Gerald Fitzgerald, and Patrick Fitzpatrick. However, the top names are not dominated by patronymic last names, including the top female name: Anna Hanna. There are many examples of this type of accidental overlap, including Avis Davis, Edith Meredith, and Milton Hamilton. It should be noted that it is possible for a last name to both end and start with a first name. And so, Rosa Rosa-Rosa is included on both lists.

4. NUMBER OF PEOPLE WITH NAMES THAT RHYME: 62,935

Using a pronouncing dictionary, I scanned the DMF for cases where the last name rhymed with the first name. The dictionary file didn’t contain every possible name, so there may be others among the 87 million; however, the more common names do appear to be included. I uncovered 16,308 different rhyming first and last names, including Florence Lawrence, Doris Morris, and Nellie Kelley. Names like this, which might be considered more melodic, seem to be more prevalent among females. Four of the top five names are female (all with first name Mary), including the most common: Mary Perry. The most common male name is John Hogan at number 2. If you’re not sold that this is a bona fide rhyme, Paul Hall and John Hahn follow at 6 and 7, respectively. There were also 158 Ronald McDonalds on the list, though in 2014 Taco Bell managed to find a couple dozen more who are still alive.

5. NUMBER OF PEOPLE WHO HAD LAST NAMES 16 CHARACTERS OR LONGER: 46

The DMF has some very rare last names that due to minimum threshold requirements don’t make it into the aggregate U.S. Census data. This includes 43 different last names that are 16 characters or longer (last names in most recent U.S. Census data max out at 15 characters). As a native of Greece, a country notorious for long last names, I had a hunch it would be a contest between Greek and Armenian last names. I was partially right in that Aghubgharehptiannej is most likely Armenian. Everybodytalksabout is Native American and Fernandezdelaportil is Spanish in origin. I excluded names with hyphens or spaces from my search, however it does appear that all three of these may have been altered to merge previously distinct segments.

The next three longest are Persian (Amirsahansouzshani), Georgian (Dzhindzhikhashvili), and Laotian (Nanthovongdouangsy). The longest Greek name in the DMF was 17 characters (Papadimitropoulos).

6. NUMBER OF PEOPLE WHO HAD ODD FIRST/LAST NAME COMBINATIONS: 272

Most of the people on the DMF were born before 1930, so names like Donald Duck (six occurrences), Homer Simpson (69 occurrences) or Joseph Stalin (one occurrence) may not have the same cultural significance for the parents who thought of these names. However, I located 20 names that would have raised eyebrows even a century ago. Finding peculiar last names is not something that can be accomplished via a simple algorithm, so I scanned the database for instances of remarkable names mentioned by Russell Ash, as well as a few of my own. The most popular is Mary Land (139 occurrences), but there's also Hazel Nutt, Robin Banks, Scott Free, and Pearly Gates.

7. NUMBER OF PEOPLE WITH UNFORTUNATE FIRST INITIALS WITH LAST NAMES: 1307

Also from Russell Ash’s list, I scanned the DMF for occurrences of 16 different unfortunate first initials and last names. At the top of the rankings are 721 B. Wares and 375 B. Quicks. O. Heck, C. Below, and T. Hee all had more than 10 occurrences.

Damian Mac Con Uladh contributed research for this article. Further information and more extensive lists of results can be found in this post at SimonKnowz.com. Social Security Death Master File courtesy of SSDMF.info.