2805380665 has 4 divisors (see below), whose sum is σ = 3366456804. Its totient is φ = 2244304528.

The previous prime is 2805380657. The next prime is 2805380693. The reversal of 2805380665 is 5660835082.

It is a happy number.

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 1138455081 + 1666925584 = 33741^2 + 40828^2 .

It is a cyclic number.

It is not a de Polignac number, because 2805380665 - 2³ = 2805380657 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 280538062 + ... + 280538071.

It is an arithmetic number, because the mean of its divisors is an integer number (841614201).

Almost surely, 2^2805380665 is an apocalyptic number.

It is an amenable number.

2805380665 is a deficient number, since it is larger than the sum of its proper divisors (561076139).

2805380665 is an equidigital number, since it uses as much as digits as its factorization.

2805380665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 561076138.

The product of its (nonzero) digits is 345600, while the sum is 43.

The square root of 2805380665 is about 52965.8443244323. The cubic root of 2805380665 is about 1410.3620057038.

The spelling of 2805380665 in words is "two billion, eight hundred five million, three hundred eighty thousand, six hundred sixty-five".