import java.util.*;

class Main {
        public static void main(String args[]) {
                try (Scanner sc = new Scanner(System.in)) {
                        long N = sc.nextLong();
                        int ans = 100000;
                        for (long i = 1; i <= Math.sqrt(N) + 1; i++) {
                                if (N % i == 0) {
                                        long M = N / i;
                                        int count = 0;
                                        while (M != 0) {
                                                M /= 10;
                                                count++;
                                        }
                                        ans = Math.min(count, ans);
                                }
                        }
                        System.out.println(ans);
                }
        }
}
/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