13911381 has 24 divisors (see below), whose sum is σ = 22198176. Its totient is φ = 8324640.

The previous prime is 13911353. The next prime is 13911383. The reversal of 13911381 is 18311931.

It is a happy number.

It is not a de Polignac number, because 13911381 - 2⁵ = 13911349 is a prime.

It is a super-2 number, since 2×13911381² = 387053042654322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13911383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7371 + ... + 9063.

It is an arithmetic number, because the mean of its divisors is an integer number (924924).

Almost surely, 2^13911381 is an apocalyptic number.

13911381 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13911381 is a deficient number, since it is larger than the sum of its proper divisors (8286795).

13911381 is a wasteful number, since it uses less digits than its factorization.

13911381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1793 (or 1790 counting only the distinct ones).

The product of its digits is 648, while the sum is 27.

The square root of 13911381 is about 3729.7963751390. The cubic root of 13911381 is about 240.5046153537.

It can be divided in two parts, 1391 and 1381, that added together give a palindrome (2772).

The spelling of 13911381 in words is "thirteen million, nine hundred eleven thousand, three hundred eighty-one".