13056640661 has 4 divisors (see below), whose sum is σ = 13077734400. Its totient is φ = 13035546924.

The previous prime is 13056640633. The next prime is 13056640687. The reversal of 13056640661 is 16604665031.

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 a de Polignac number, because none of the positive numbers 2^k-13056640661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13056640061) 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, 10545941 + ... + 10547178.

It is an arithmetic number, because the mean of its divisors is an integer number (3269433600).

Almost surely, 2^13056640661 is an apocalyptic number.

It is an amenable number.

13056640661 is a deficient number, since it is larger than the sum of its proper divisors (21093739).

13056640661 is an equidigital number, since it uses as much as digits as its factorization.

13056640661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21093738.

The product of its (nonzero) digits is 77760, while the sum is 38.

The spelling of 13056640661 in words is "thirteen billion, fifty-six million, six hundred forty thousand, six hundred sixty-one".