import java.util.Scanner;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int min = 10;
        long B = 1;
        for(long A = 1;A * A <= N;A++){
            if(N % A == 0){
                B = N / A;
            }
            if(digits(B) < min){
                min = digits(B);
            }
        }
        System.out.println(min);
    }
    public static int digits(long max){
        int count = 0;
        while(max != 0){
            max /= 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