13688641805549 has 4 divisors (see below), whose sum is σ = 14409096637440. Its totient is φ = 12968186973660.

The previous prime is 13688641805543. The next prime is 13688641805551. The reversal of 13688641805549 is 94550814688631.

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.

It is a cyclic number.

It is not a de Polignac number, because 13688641805549 - 2²⁸ = 13688373370093 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13688641805543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 360227415917 + ... + 360227415954.

It is an arithmetic number, because the mean of its divisors is an integer number (3602274159360).

Almost surely, 2^{13688641805549} is an apocalyptic number.

13688641805549 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

13688641805549 is a deficient number, since it is larger than the sum of its proper divisors (720454831891).

13688641805549 is an equidigital number, since it uses as much as digits as its factorization.

13688641805549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720454831890.

The product of its (nonzero) digits is 199065600, while the sum is 68.

The spelling of 13688641805549 in words is "thirteen trillion, six hundred eighty-eight billion, six hundred forty-one million, eight hundred five thousand, five hundred forty-nine".