13688581 has 4 divisors (see below), whose sum is σ = 13787200. Its totient is φ = 13589964.

The previous prime is 13688573. The next prime is 13688593. The reversal of 13688581 is 18588631.

13688581 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, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18588631 = 19 ⋅978349.

It is a cyclic number.

It is not a de Polignac number, because 13688581 - 2³ = 13688573 is a prime.

It is a super-2 number, since 2×13688581² = 374754499587122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13688501) 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, 49101 + ... + 49378.

It is an arithmetic number, because the mean of its divisors is an integer number (3446800).

Almost surely, 2^13688581 is an apocalyptic number.

It is an amenable number.

13688581 is a deficient number, since it is larger than the sum of its proper divisors (98619).

13688581 is an equidigital number, since it uses as much as digits as its factorization.

13688581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98618.

The product of its digits is 46080, while the sum is 40.

The square root of 13688581 is about 3699.8082382740. The cubic root of 13688581 is about 239.2137522714.

The spelling of 13688581 in words is "thirteen million, six hundred eighty-eight thousand, five hundred eighty-one".