26831707561 has 4 divisors (see below), whose sum is σ = 26930717824. Its totient is φ = 26732697300.

The previous prime is 26831707547. The next prime is 26831707577. The reversal of 26831707561 is 16570713862.

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: 16570713862 = 2 ⋅8285356931.

It is a cyclic number.

It is not a de Polignac number, because 26831707561 - 2⁷ = 26831707433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26831707361) 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, 49504725 + ... + 49505266.

It is an arithmetic number, because the mean of its divisors is an integer number (6732679456).

Almost surely, 2^26831707561 is an apocalyptic number.

It is an amenable number.

26831707561 is a deficient number, since it is larger than the sum of its proper divisors (99010263).

26831707561 is an equidigital number, since it uses as much as digits as its factorization.

26831707561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99010262.

The product of its (nonzero) digits is 423360, while the sum is 46.

The spelling of 26831707561 in words is "twenty-six billion, eight hundred thirty-one million, seven hundred seven thousand, five hundred sixty-one".