The latest line should be

    n = 19227; k = 6018; Nx = 10^6;
    N[CDF[HypergeometricDistribution[n, k, Nx], 200], 50] - 
     N[CDF[HypergeometricDistribution[n, k, Nx], 0], 50]

> `0.000330001`

See [Wiki](https://en.wikipedia.org/wiki/Cumulative_distribution_function) for info.