This number is a composite.

+ The first known titanic prime was found by Alexander Hurwitz in 1961.

+ 1961 was the most recent strobogrammatic year. Note that the sum of its prime factors is 90, which contains the necessary digits to form the next such year, i.e., 6009. [Honaker]

+ (1+9+6+1)*1961 + 1*9*6*1, (1!*9!*6!*1!)*1961 - 1, & (1*9*6*1)!*1961*prime(1961) + 1, are primes. Note that 1961 is the smallest number with such properties. [Firoozbakht]

+ The second smallest strobogrammatic tnaillirb, i.e., a brilliant number whose reversal is a different brilliant number. Note that it is a permutation of 1691, which is the smallest strobogrammatic tnaillirb. [Post]

+ The only strobogrammatic tnaillirb concatenated from two double-digit primes and also the only strobogrammatic tnaillirb with prime-digit prime factors, 1961 = 37*53. [Loungrides]

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