13157691 has 4 divisors (see below), whose sum is σ = 17543592. Its totient is φ = 8771792.

The previous prime is 13157689. The next prime is 13157701. The reversal of 13157691 is 19675131.

It is a happy number.

13157691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 13157691 - 2¹ = 13157689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13157611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2192946 + ... + 2192951.

It is an arithmetic number, because the mean of its divisors is an integer number (4385898).

Almost surely, 2^13157691 is an apocalyptic number.

13157691 is a deficient number, since it is larger than the sum of its proper divisors (4385901).

13157691 is an equidigital number, since it uses as much as digits as its factorization.

13157691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4385900.

The product of its digits is 5670, while the sum is 33.

The square root of 13157691 is about 3627.3531672557. The cubic root of 13157691 is about 236.0803793522.

The spelling of 13157691 in words is "thirteen million, one hundred fifty-seven thousand, six hundred ninety-one".