805831609 has 4 divisors (see below), whose sum is σ = 879089040. Its totient is φ = 732574180.

The previous prime is 805831573. The next prime is 805831627. The reversal of 805831609 is 906138508.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 805831609 - 2¹¹ = 805829561 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (805831669) 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, 36628699 + ... + 36628720.

It is an arithmetic number, because the mean of its divisors is an integer number (219772260).

Almost surely, 2^805831609 is an apocalyptic number.

It is an amenable number.

805831609 is a deficient number, since it is larger than the sum of its proper divisors (73257431).

805831609 is a wasteful number, since it uses less digits than its factorization.

805831609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73257430.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 805831609 is about 28387.1733182436. The cubic root of 805831609 is about 930.5679688575.

The spelling of 805831609 in words is "eight hundred five million, eight hundred thirty-one thousand, six hundred nine".