2565805 has 12 divisors (see below), whose sum is σ = 3385116. Its totient is φ = 1865600.

The previous prime is 2565799. The next prime is 2565809. The reversal of 2565805 is 5085652.

It can be written as a sum of positive squares in 2 ways, for example, as 1920996 + 644809 = 1386^2 + 803^2 .

It is not a de Polignac number, because 2565805 - 2¹³ = 2557613 is a prime.

It is a Duffinian number.

2565805 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2565809) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1516 + ... + 2725.

It is an arithmetic number, because the mean of its divisors is an integer number (282093).

2^2565805 is an apocalyptic number.

It is an amenable number.

2565805 is a deficient number, since it is larger than the sum of its proper divisors (819311).

2565805 is a wasteful number, since it uses less digits than its factorization.

2565805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4268 (or 4257 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 31.

The square root of 2565805 is about 1601.8130352822. The cubic root of 2565805 is about 136.9013977845.

The spelling of 2565805 in words is "two million, five hundred sixty-five thousand, eight hundred five".