805768409 has 4 divisors (see below), whose sum is σ = 807026100. Its totient is φ = 804510720.

The previous prime is 805768387. The next prime is 805768417. The reversal of 805768409 is 904867508.

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 527712784 + 278055625 = 22972^2 + 16675^2 .

It is a cyclic number.

It is not a de Polignac number, because 805768409 - 2²⁴ = 788991193 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (805768489) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 627884 + ... + 629165.

It is an arithmetic number, because the mean of its divisors is an integer number (201756525).

Almost surely, 2^805768409 is an apocalyptic number.

It is an amenable number.

805768409 is a deficient number, since it is larger than the sum of its proper divisors (1257691).

805768409 is a wasteful number, since it uses less digits than its factorization.

805768409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1257690.

The product of its (nonzero) digits is 483840, while the sum is 47.

The square root of 805768409 is about 28386.0601176000. The cubic root of 805768409 is about 930.5436406014.

Subtracting 805768409 from its reverse (904867508), we obtain a palindrome (99099099).

The spelling of 805768409 in words is "eight hundred five million, seven hundred sixty-eight thousand, four hundred nine".