25656676645 has 4 divisors (see below), whose sum is σ = 30788011980. Its totient is φ = 20525341312.

The previous prime is 25656676613. The next prime is 25656676649. The reversal of 25656676645 is 54667665652.

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 11430389569 + 14226287076 = 106913^2 + 119274^2 .

It is a cyclic number.

It is not a de Polignac number, because 25656676645 - 2⁵ = 25656676613 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25656676645.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25656676649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2565667660 + ... + 2565667669.

It is an arithmetic number, because the mean of its divisors is an integer number (7697002995).

Almost surely, 2^25656676645 is an apocalyptic number.

It is an amenable number.

25656676645 is a deficient number, since it is larger than the sum of its proper divisors (5131335335).

25656676645 is an equidigital number, since it uses as much as digits as its factorization.

25656676645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5131335334.

The product of its digits is 54432000, while the sum is 58.

The spelling of 25656676645 in words is "twenty-five billion, six hundred fifty-six million, six hundred seventy-six thousand, six hundred forty-five".