
Curios:
Curios Search:
Participate: 
A palindrome that produces a Composed prime: 434 = 2 x 7 x 31 and 4^{2} + 3^{7} + 4^{31} = 4611686018427390107 is prime. [De Geest] 434 is also the sum of the cubes of the digits of the emirp 347. [Trotter] The smallest composite number n which satisfy the equation sigma(n+2) = sigma(n)+2, where sigma(n) is sum of divisors of n. [Gupta]
Prime Curios! © 20002018 (all rights
reserved)
privacy statement
