#include <stdio.h>
int main(void){
    int N;
    int count = 0;
    
    scanf("%d",&N);

    for(int i = N-100; i <= N+100; i++){
        for(int j = 1; j <= i; j++){
            if(i % j == 0){
                count++;
            }
        }
        if(count > 2){
            printf("%d\n",i);
            return 0;
        }
        count = 0;
    }

    return 0;
}