Freud was haunted by certain numbers.

LETTERS FROM FREUD TO Jung (From Memories, Dreams and Reflections) Vienna. IX, Berggasse 19 April 16, 1909 ......"Now I shall exercise the privilege of my years to turn loquacious and tell you about one more matter between heaven and earth which cannot be understood. A few years ago I took it into my head that I would die between the ages of 61 and 62, which at that time seemed to leave me a decent period of grace. (Today that leaves me only eight years still to go.) Shortly afterward I made a trip to Greece with my brother, and it was absolutely uncanny to see how the number 61 or 6o in conjunction with 1 and 2, kept cropping up on anything that had a number, especially on vehicles. I conscientiously noted down these occasions. By the time we came to Athens, I was feeling depressed. At our hotel we were assigned rooms on the second floor. and I hoped I could breathe again-at least there could be no chance of No. 61. However, it turned out that my room was No.31 (which with fatalistic license, I regarded as after all half of 61-62). This wilier and nimbler figure proved to be even better at dogging me than the first. From that day until very recently the number 31 remained faithful to me, with a 2 all too readily associated with it. But since I also have in my psychic system regions in which I am merely avid for knowledge and not at all superstitious, I have attempted to analyze this conviction. Here it is. My conviction began in 1899. Two events coincided at that time. The first was my writing The lnterpretation of Dreams (which, you know, is dated ahead to 1900); the second. my being assigned a new telephone number, which I have to this day 14362. It is easy to establish the link between these two fact: in the year1899, when I wrote The Interpretation of Dreams, I was 43 years old. What should be more obvious than that the other figures in my telephone number were intended to signify the end of my life hence, 61 or 62? Suddenly there appears a method in this madness. The superstition that I would die between 61 and 62 turns out to be equivalent to the conviction that with the book on dreams I had completed my life work, needed to say no more and could die in peace. You will grant that after this analysis it no longer sounds so nonsensical. Incidentally, the influence of Wilhelm Fliess plays a part in this; the superstition dates from the year of his attack on me. Here is another instance where you will find confirmation of the specifically Jewish character of my mysticism. Apart from this, I only want to say that adventures such as mine with the number 62 can be explained by two things. The first is an enormously intensified alertness on the part of the unconscious, so that one is led like Faust to see a Helen in every woman. The second is the undeniable co-operation of ‘chance’ which plays the same role in the formation of delusions as somatic co-operation in hysterical symptoms or linguistic co-operation in puns. I therefore look forward to hearing more about your investigations of the spook-complex, my interest being the interest one has in a lovely delusion which one does not share oneself. With cordial regards to Yourself your wife and children, Yours, Freud. ..." This is a special kind of 'coincidence' isn't it, perhaps it is good to know that Freud analyzed his numbers as significant (possibly) details about himself.