25565256551 has 8 divisors (see below), whose sum is σ = 25755354240. Its totient is φ = 25375247352.

The previous prime is 25565256529. The next prime is 25565256589. The reversal of 25565256551 is 15565256552.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25565256551 - 2⁶ = 25565256487 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25565256496 and 25565256505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25565256151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 628436 + ... + 667878.

It is an arithmetic number, because the mean of its divisors is an integer number (3219419280).

Almost surely, 2^25565256551 is an apocalyptic number.

25565256551 is a deficient number, since it is larger than the sum of its proper divisors (190097689).

25565256551 is a wasteful number, since it uses less digits than its factorization.

25565256551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44245.

The product of its digits is 2250000, while the sum is 47.

Subtracting from 25565256551 its reverse (15565256552), we obtain a palindrome (9999999999).

The spelling of 25565256551 in words is "twenty-five billion, five hundred sixty-five million, two hundred fifty-six thousand, five hundred fifty-one".