using Open.Numeric.Primes;

Number.IsPrime(8592868089022906369); // true

Prime.Factors(12); // 2, 2, 3

Prime.CommonFactors(84, 756, 108); // 2, 2, 3

Prime.GreatestFactor(84, 756, 108); // 12

// Will list the first 1000 primes.
foreach(var prime in Prime.Numbers.Take(1000))
{
    Console.Write(prime);
}

// Will list the first 1000 primes greater than (or equal to) 10,000.
foreach(var prime in Prime.Numbers.StartingAt(10000).Take(100))
{
    Console.Write(prime);
}

using Open.Numeric.Primes.Extensions;

8592868089022906369.IsPrime(); // true