import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextLong();
        long min = 0;
        for(int i = (int) Math.sqrt(n); i>0; --i){
                if(n%i==0){
                    min = n/i;
                    break;
                }
        }
        System.out.println(getNums(min));
    }
    static int getNums(long n){
        int count  = 0;
        while(n>0){
            n /= 10;
            count++;
        }
        return count;
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz