804040639 has 4 divisors (see below), whose sum is σ = 806882056. Its totient is φ = 801199224.

The previous prime is 804040607. The next prime is 804040649. The reversal of 804040639 is 936040408.

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

It is a cyclic number.

It is not a de Polignac number, because 804040639 - 2⁵ = 804040607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (804040649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1420284 + ... + 1420849.

It is an arithmetic number, because the mean of its divisors is an integer number (201720514).

Almost surely, 2^804040639 is an apocalyptic number.

804040639 is a deficient number, since it is larger than the sum of its proper divisors (2841417).

804040639 is a wasteful number, since it uses less digits than its factorization.

804040639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2841416.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 804040639 is about 28355.6103619725. The cubic root of 804040639 is about 929.8780581628.

The spelling of 804040639 in words is "eight hundred four million, forty thousand, six hundred thirty-nine".