The latest line should be
n = 19227; k = 6018; Nx = 10^6;
N[CDF[HypergeometricDistribution[n, k, Nx], 200], 100] -
N[CDF[HypergeometricDistribution[n, k, Nx], 1], 100]
0.9999999999998023447442687988099080331358471319483455578402776321973499999999999980234474426879880990803313584713194819457153196994629316 2258123865849703518147523080727338734132748161581793705151966009
See Wiki for info.