80804040809 has 4 divisors (see below), whose sum is σ = 81420865680. Its totient is φ = 80187215940.

The previous prime is 80804040803. The next prime is 80804040859. The reversal of 80804040809 is 90804040808.

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 a de Polignac number, because none of the positive numbers 2^k-80804040809 is a prime.

It is a super-2 number, since 2×80804040809² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (80804040803) 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, 308412239 + ... + 308412500.

It is an arithmetic number, because the mean of its divisors is an integer number (20355216420).

Almost surely, 2^80804040809 is an apocalyptic number.

It is an amenable number.

80804040809 is a deficient number, since it is larger than the sum of its proper divisors (616824871).

80804040809 is a wasteful number, since it uses less digits than its factorization.

80804040809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 616824870.

The product of its (nonzero) digits is 73728, while the sum is 41.

Subtracting 80804040809 from its reverse (90804040808), we obtain a palindrome (9999999999).

The spelling of 80804040809 in words is "eighty billion, eight hundred four million, forty thousand, eight hundred nine".