13681591 has 24 divisors (see below), whose sum is σ = 17811360. Its totient is φ = 10274880.

The previous prime is 13681589. The next prime is 13681621. The reversal of 13681591 is 19518631.

It is not a de Polignac number, because 13681591 - 2¹ = 13681589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13681511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24285 + ... + 24841.

It is an arithmetic number, because the mean of its divisors is an integer number (742140).

Almost surely, 2^13681591 is an apocalyptic number.

13681591 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

13681591 is a deficient number, since it is larger than the sum of its proper divisors (4129769).

13681591 is a wasteful number, since it uses less digits than its factorization.

13681591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 615 (or 604 counting only the distinct ones).

The product of its digits is 6480, while the sum is 34.

The square root of 13681591 is about 3698.8634740958. The cubic root of 13681591 is about 239.1730276015.

The spelling of 13681591 in words is "thirteen million, six hundred eighty-one thousand, five hundred ninety-one".