1961

This number is a composite.

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

(1+9+6+1)*1961 + 1*9*6*1, (1!*9!*6!*1!)*1961 - 1, & (1*9*6*1)!*1961*prime(1961) + 1, are primes. Note that 1961 is the smallest number with such properties. [Firoozbakht]