2565665 has 16 divisors (see below), whose sum is σ = 3283200. Its totient is φ = 1919232.

The previous prime is 2565649. The next prime is 2565671. The reversal of 2565665 is 5665652.

It is a cyclic number.

It is not a de Polignac number, because 2565665 - 2⁴ = 2565649 is a prime.

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10616 + ... + 10854.

It is an arithmetic number, because the mean of its divisors is an integer number (205200).

2^2565665 is an apocalyptic number.

It is an amenable number.

2565665 is a deficient number, since it is larger than the sum of its proper divisors (717535).

2565665 is a wasteful number, since it uses less digits than its factorization.

2565665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376.

The product of its digits is 54000, while the sum is 35.

The square root of 2565665 is about 1601.7693342051. The cubic root of 2565665 is about 136.8989077870.

The spelling of 2565665 in words is "two million, five hundred sixty-five thousand, six hundred sixty-five".