1

This number is a unit (so is neither prime nor composite).

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

Bertrand's Postulate guarantees that in every base there is at least one prime of any given length beginning with the digit 1, and Benford's Law tells us that primes with leading digit 1 occur more often than primes beginning with any other digit in all bases. [Rupinski]