25135810561 has 4 divisors (see below), whose sum is σ = 25246541232. Its totient is φ = 25025079892.

The previous prime is 25135810541. The next prime is 25135810573. The reversal of 25135810561 is 16501853152.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25135810561 - 2¹³ = 25135802369 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25135810561.

It is not an unprimeable number, because it can be changed into a prime (25135810501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55364995 + ... + 55365448.

It is an arithmetic number, because the mean of its divisors is an integer number (6311635308).

Almost surely, 2^25135810561 is an apocalyptic number.

It is an amenable number.

25135810561 is a deficient number, since it is larger than the sum of its proper divisors (110730671).

25135810561 is a wasteful number, since it uses less digits than its factorization.

25135810561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110730670.

The product of its (nonzero) digits is 36000, while the sum is 37.

The spelling of 25135810561 in words is "twenty-five billion, one hundred thirty-five million, eight hundred ten thousand, five hundred sixty-one".