25760508661 has 4 divisors (see below), whose sum is σ = 25924588492. Its totient is φ = 25596428832.

The previous prime is 25760508623. The next prime is 25760508673. The reversal of 25760508661 is 16680506752.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13428406161 + 12332102500 = 115881^2 + 111050^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25760508661 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 (25760508611) 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, 82039680 + ... + 82039993.

It is an arithmetic number, because the mean of its divisors is an integer number (6481147123).

Almost surely, 2^25760508661 is an apocalyptic number.

It is an amenable number.

25760508661 is a deficient number, since it is larger than the sum of its proper divisors (164079831).

25760508661 is a wasteful number, since it uses less digits than its factorization.

25760508661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164079830.

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 25760508661 in words is "twenty-five billion, seven hundred sixty million, five hundred eight thousand, six hundred sixty-one".