2505665 has 4 divisors (see below), whose sum is σ = 3006804. Its totient is φ = 2004528.

The previous prime is 2505641. The next prime is 2505673. The reversal of 2505665 is 5665052.

2505665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 579121 + 1926544 = 761^2 + 1388^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2505665 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250562 + ... + 250571.

It is an arithmetic number, because the mean of its divisors is an integer number (751701).

2^2505665 is an apocalyptic number.

It is an amenable number.

2505665 is a deficient number, since it is larger than the sum of its proper divisors (501139).

2505665 is an equidigital number, since it uses as much as digits as its factorization.

2505665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501138.

The product of its (nonzero) digits is 9000, while the sum is 29.

The square root of 2505665 is about 1582.9292466816. The cubic root of 2505665 is about 135.8233179998.

The spelling of 2505665 in words is "two million, five hundred five thousand, six hundred sixty-five".