This number is a composite.

+ 102 = 2 * 3 * 17. The number and sum of its digits is equal to the number of its different prime factors. It is the smallest 3-almost prime with this property. [Capelle]

+ There are 102 distinct digit primes p for which 10*p+1, 10*p+3, 10*p+7 and 10*p+9 are primes. [Gupta]

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