2565638751 has 16 divisors (see below), whose sum is σ = 3687205760. Its totient is φ = 1577478240.

The previous prime is 2565638749. The next prime is 2565638807. The reversal of 2565638751 is 1578365652.

It is not a de Polignac number, because 2565638751 - 2¹ = 2565638749 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 2565638751.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2565638701) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 17580 + ... + 73758.

It is an arithmetic number, because the mean of its divisors is an integer number (230450360).

Almost surely, 2^2565638751 is an apocalyptic number.

2565638751 is a deficient number, since it is larger than the sum of its proper divisors (1121567009).

2565638751 is a wasteful number, since it uses less digits than its factorization.

2565638751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57366.

The product of its digits is 1512000, while the sum is 48.

The square root of 2565638751 is about 50652.1347131589. The cubic root of 2565638751 is about 1368.9844092017.

The spelling of 2565638751 in words is "two billion, five hundred sixty-five million, six hundred thirty-eight thousand, seven hundred fifty-one".