13357981 has 16 divisors (see below), whose sum is σ = 16551808. Its totient is φ = 10497600.

The previous prime is 13357973. The next prime is 13357997. The reversal of 13357981 is 18975331.

It is a happy number.

13357981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a 3-Lehmer number, since φ(13357981) divides (13357981-1)³.

It is a cyclic number.

It is not a de Polignac number, because 13357981 - 2³ = 13357973 is a prime.

It is a super-2 number, since 2×13357981² = 356871312792722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 13357981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13357681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16066 + ... + 16876.

It is an arithmetic number, because the mean of its divisors is an integer number (1034488).

It is a Poulet number, since it divides 2^13357980-1.

Almost surely, 2^13357981 is an apocalyptic number.

It is an amenable number.

13357981 is a deficient number, since it is larger than the sum of its proper divisors (3193827).

13357981 is a wasteful number, since it uses less digits than its factorization.

13357981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1012.

The product of its digits is 22680, while the sum is 37.

The square root of 13357981 is about 3654.8571791521. The cubic root of 13357981 is about 237.2722455576.

It can be divided in two parts, 1335 and 7981, that added together give a triangular number (9316 = T₁₃₆).

The spelling of 13357981 in words is "thirteen million, three hundred fifty-seven thousand, nine hundred eighty-one".