25239836465 has 4 divisors (see below), whose sum is σ = 30287803764. Its totient is φ = 20191869168.

The previous prime is 25239836443. The next prime is 25239836477. The reversal of 25239836465 is 56463893252.

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 12801564736 + 12438271729 = 113144^2 + 111527^2 .

It is a cyclic number.

It is not a de Polignac number, because 25239836465 - 2¹² = 25239832369 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2523983642 + ... + 2523983651.

It is an arithmetic number, because the mean of its divisors is an integer number (7571950941).

Almost surely, 2^25239836465 is an apocalyptic number.

It is an amenable number.

25239836465 is a deficient number, since it is larger than the sum of its proper divisors (5047967299).

25239836465 is an equidigital number, since it uses as much as digits as its factorization.

25239836465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5047967298.

The product of its digits is 9331200, while the sum is 53.

The spelling of 25239836465 in words is "twenty-five billion, two hundred thirty-nine million, eight hundred thirty-six thousand, four hundred sixty-five".