2565751 has 4 divisors (see below), whose sum is σ = 2589400. Its totient is φ = 2542104.

The previous prime is 2565713. The next prime is 2565757. The reversal of 2565751 is 1575652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2565751 - 2⁹ = 2565239 is a prime.

It is a Duffinian number.

2565751 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2565757) 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, 11661 + ... + 11878.

It is an arithmetic number, because the mean of its divisors is an integer number (647350).

2^2565751 is an apocalyptic number.

2565751 is a deficient number, since it is larger than the sum of its proper divisors (23649).

2565751 is a wasteful number, since it uses less digits than its factorization.

2565751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23648.

The product of its digits is 10500, while the sum is 31.

The square root of 2565751 is about 1601.7961792937. The cubic root of 2565751 is about 136.9004373676.

Subtracting from 2565751 its reverse (1575652), we obtain a palindrome (990099).

The spelling of 2565751 in words is "two million, five hundred sixty-five thousand, seven hundred fifty-one".