25628186561 has 16 divisors (see below), whose sum is σ = 26466607440. Its totient is φ = 24800762880.

The previous prime is 25628186527. The next prime is 25628186587. The reversal of 25628186561 is 16568182652.

It can be written as a sum of positive squares in 8 ways, for example, as 16191035536 + 9437151025 = 127244^2 + 97145^2 .

It is a cyclic number.

It is not a de Polignac number, because 25628186561 - 2¹⁰ = 25628185537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25628186161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2564771 + ... + 2574743.

It is an arithmetic number, because the mean of its divisors is an integer number (1654162965).

Almost surely, 2^25628186561 is an apocalyptic number.

It is an amenable number.

25628186561 is a deficient number, since it is larger than the sum of its proper divisors (838420879).

25628186561 is a wasteful number, since it uses less digits than its factorization.

25628186561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10516.

The product of its digits is 1382400, while the sum is 50.

The spelling of 25628186561 in words is "twenty-five billion, six hundred twenty-eight million, one hundred eighty-six thousand, five hundred sixty-one".