25528747165 has 4 divisors (see below), whose sum is σ = 30634496604. Its totient is φ = 20422997728.

The previous prime is 25528747147. The next prime is 25528747169. The reversal of 25528747165 is 56174782552.

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 12746635801 + 12782111364 = 112901^2 + 113058^2 .

It is a cyclic number.

It is not a de Polignac number, because 25528747165 - 2⁷ = 25528747037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25528747169) 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, 2552874712 + ... + 2552874721.

It is an arithmetic number, because the mean of its divisors is an integer number (7658624151).

Almost surely, 2^25528747165 is an apocalyptic number.

It is an amenable number.

25528747165 is a deficient number, since it is larger than the sum of its proper divisors (5105749439).

25528747165 is an equidigital number, since it uses as much as digits as its factorization.

25528747165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5105749438.

The product of its digits is 4704000, while the sum is 52.

The spelling of 25528747165 in words is "twenty-five billion, five hundred twenty-eight million, seven hundred forty-seven thousand, one hundred sixty-five".