Ignoring the century in the year, I love the coincidence that this question was first asked in the year '54 and in "Hitchhiker's", it's said that 6x9 and 42 are the same. In fact they are if 6x9 is base 10 (6x9=54), and 42 is base 13 (4x13+2 = 54).
So, we get three coincidences: This question was asked in '54 ; "Hitchhiker's" said the answer to the meaning of life is 54 (6x9, 42 base 13); and best of all, 42 was the last number solved. And if you want to add one more coincidence, this was solved in the year '19 (connecting 19 and 54).
All irrelevant coincidences applied with hindsight, but fun.
(Douglas Adams claimed that 42 was a randomly chosen number, but I'd argue his subconscious had been processing the idea for a while and gave him a number with a meaning. We just don't know which is the correct meaning.)