2565639 has 6 divisors (see below), whose sum is σ = 3705936. Its totient is φ = 1710420.

The previous prime is 2565611. The next prime is 2565643. The reversal of 2565639 is 9365652.

It is not a de Polignac number, because 2565639 - 2⁸ = 2565383 is a prime.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2565649) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 142527 + ... + 142544.

It is an arithmetic number, because the mean of its divisors is an integer number (617656).

2^2565639 is an apocalyptic number.

2565639 is a deficient number, since it is larger than the sum of its proper divisors (1140297).

2565639 is a wasteful number, since it uses less digits than its factorization.

2565639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285077 (or 285074 counting only the distinct ones).

The product of its digits is 48600, while the sum is 36.

The square root of 2565639 is about 1601.7612181596. The cubic root of 2565639 is about 136.8984453489.

The spelling of 2565639 in words is "two million, five hundred sixty-five thousand, six hundred thirty-nine".