13231691 has 4 divisors (see below), whose sum is σ = 14434584. Its totient is φ = 12028800.

The previous prime is 13231679. The next prime is 13231703. The reversal of 13231691 is 19613231.

13231691 = 765² + 766² + ... + 786².

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

It is an interprime number because it is at equal distance from previous prime (13231679) and next prime (13231703).

It is a cyclic number.

It is not a de Polignac number, because 13231691 - 2¹⁰ = 13230667 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13231691.

It is not an unprimeable number, because it can be changed into a prime (13231651) 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 3 ways as a sum of consecutive naturals, for example, 601430 + ... + 601451.

It is an arithmetic number, because the mean of its divisors is an integer number (3608646).

Almost surely, 2^13231691 is an apocalyptic number.

13231691 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

13231691 is a deficient number, since it is larger than the sum of its proper divisors (1202893).

13231691 is a wasteful number, since it uses less digits than its factorization.

13231691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1202892.

The product of its digits is 972, while the sum is 26.

The square root of 13231691 is about 3637.5391406829. The cubic root of 13231691 is about 236.5221311050.

The spelling of 13231691 in words is "thirteen million, two hundred thirty-one thousand, six hundred ninety-one".