26561166271 has 4 divisors (see below), whose sum is σ = 26730345832. Its totient is φ = 26391986712.

The previous prime is 26561166251. The next prime is 26561166341. The reversal of 26561166271 is 17266116562.

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

It is a cyclic number.

It is not a de Polignac number, because 26561166271 - 2²³ = 26552777663 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 (26561166251) 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, 84589545 + ... + 84589858.

It is an arithmetic number, because the mean of its divisors is an integer number (6682586458).

Almost surely, 2^26561166271 is an apocalyptic number.

26561166271 is a deficient number, since it is larger than the sum of its proper divisors (169179561).

26561166271 is a wasteful number, since it uses less digits than its factorization.

26561166271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169179560.

The product of its digits is 181440, while the sum is 43.

The spelling of 26561166271 in words is "twenty-six billion, five hundred sixty-one million, one hundred sixty-six thousand, two hundred seventy-one".