This number is a prime.
2777 = 12 + 23 + 35 + 47 + 511 + 613 + 717 + 819, where each addend is the concatenation of n and the nth prime. (2777 is the smallest prime formed in this manner.) [Poo Sung]
Inserting this prime in-between two reversals of p^n we find the reversal of another power of p, i.e., 2^4=16,
2^24=16777216 (case p=2, n=4), and R(2^24)=61277761. [Loungrides]
The so-called “doomsday argument” holds that there is a 50%
chance that the end of human life will come before the year
(There are 2 curios for this number that have not yet been approved by an editor.)
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