SS Ellan Vannin (1854) her general exterior being similar to the "Countess of Ellesmere." In fact she was built very much after the model of that vessel, but with the additional requirements to adapt her for sea-going purposes in the challenging conditions around the Isle of Man. Clinker built, "Ellan Vannin" was rigged as a two mast steamer with two white painted funnels and with a full length female figurehead sitting on a rock adorned with a castellated crown. "Ellan Vannin" was well appointed for the carriage of passengers with accommodation for 91 First Class and 195 Second Class. Her after saloon was in
Largest known prime number Largest known prime number The largest known prime number () is 2 − 1, a number with 23,249,425 digits. It was found by the Great Internet Mersenne Prime Search (GIMPS) in 2017. Euclid proved that there is no largest prime number, and many mathematicians and hobbyists continue to search for large prime numbers. Many of the largest known primes are Mersenne primes. , the seven largest known primes are Mersenne primes. The last sixteen record primes were Mersenne primes. The fast Fourier transform implementation of the Lucas–Lehmer primality test for Mersenne numbers is fast compared to other known primality tests