1155
number 1155
36
It is 11 which is a prime number whose factors are itself and one
2 and 3 are the smallest prime numbers. So answer is 2^3 * 3^3 = 216
That number is 724.
23
72
It is a Prime Number.
There are infinitely many prime numbers, and also infinitely many twin primes so there is no answer to the question.
The smallest prime number, of course, is 2. The smallest prime number whose digits add up to 2 is, of course, 2. The next-smallest is 11. It is left as an exercise for the reader to determine whether the other numbers whose digits add up to 2 (e.g. 101, 1001, 10001) are prime.
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