25805825251 has 4 divisors (see below), whose sum is σ = 27164026600. Its totient is φ = 24447623904.

The previous prime is 25805825209. The next prime is 25805825261. The reversal of 25805825251 is 15252850852.

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 25805825251 - 2¹⁵ = 25805792483 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25805825198 and 25805825207.

It is not an unprimeable number, because it can be changed into a prime (25805825261) 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, 679100646 + ... + 679100683.

It is an arithmetic number, because the mean of its divisors is an integer number (6791006650).

Almost surely, 2^25805825251 is an apocalyptic number.

25805825251 is a deficient number, since it is larger than the sum of its proper divisors (1358201349).

25805825251 is a wasteful number, since it uses less digits than its factorization.

25805825251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1358201348.

The product of its (nonzero) digits is 320000, while the sum is 43.

The spelling of 25805825251 in words is "twenty-five billion, eight hundred five million, eight hundred twenty-five thousand, two hundred fifty-one".