Check out this link for the number of words for each letter count.
The numbers are a tad bit lower than you reference.
https://www.quora.com/How-many-4-let...ist-in-English
How many of words are there of different sizes in that dictionary?
# Case-sensitive results
# To address why there are 52 1-letter words.
# macOSX considers each letter a separate word
# so -> 26 * 2 ( for upper and lower cases)
1 letter words -> 52
2 letter words -> 160
3 letter words -> 1420
5 letter words -> 10230
4 letter words -> 5272
8 letter words -> 29989
7 letter words -> 23869
9 letter words -> 32403
6 letter words -> 17706
11 letter words -> 26013
10 letter words -> 30878
12 letter words -> 20462
14 letter words -> 9765
16 letter words -> 3377
15 letter words -> 5925
20 letter words -> 198
19 letter words -> 428
17 letter words -> 1813
13 letter words -> 14939
18 letter words -> 842
21 letter words -> 82
22 letter words -> 41
23 letter words -> 17
24 letter words -> 5
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How many of those words would people want as their name? I suspect those numbers are a small fraction of these numbers.