19

This number is a prime.

Just showing those entries submitted by 'Gupta': (Click here to show all)

+ 19 is the smallest prime whose reversal is composite. [Gupta]

+ The smallest number (coincidentally prime) with an additive persistence of 2. [Gupta]

+ The only prime that is equal to the difference of two prime cubes. [Gupta]

+ The last 19 digits of 17^18 is prime. [Gupta]

+ The only known prime formed from concatenation of first n Kaprekar numbers (case n=2). [Gupta]

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