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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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