\begin{array}{c} \color{#FFFFFFff}{H}\color{#E7E7E7ff}{o}\color{#CFCFCFff}{r}\color{#B7B7B7ff}{i}\color{#9F9F9Fff}{z}\color{#878787ff}{o}\color{#6F6F6Fff}{n} \end{array} $\\$

# Horizon
N = 1000000
a = [1] * (N + 1)

def sang():
    a[0] = a[1] = 0 
    for i in range(2, int(N**0.5) + 1):
        if a[i]:
            for j in range(i * i, N + 1, i):
                a[j] = 0
                

n = int(input())
if a[n]:
    print("La so nguyen to")
else:
    print("Khong la so nguyen to")