274

This number is a composite.

(274 - 2)² + (274 - 7)⁷ + (274 - 4)⁴ is prime. [Opao]

The 274th Lucas number plus 274 is prime. [Opao]

4^4*14^14*274^274 + 1 is the largest non-titanic prime, (687-digit), of form 4^4*14^14*274^274*…*a(n-1)^a(n-1)* a(n)^(a(n)+1, where the bases and exponents are composite, a(n) and 4^4*14^14*…* a(n-1)^a(n-1)*a(n)^a(n)+1 are prime, a(n)>a(n-1), and a(n) is minimal. Note that the previous such primes are: a(1) = 4^4+1 = 257 and a(2) = 4^4*14^14+1 = 2844673747342852097. [Loungrides]