80812809 has 72 divisors (see below), whose sum is σ = 153867168. Its totient is φ = 41912640.

The previous prime is 80812807. The next prime is 80812817. The reversal of 80812809 is 90821808.

It is not a de Polignac number, because 80812809 - 2¹ = 80812807 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (80812807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 130669 + ... + 131285.

It is an arithmetic number, because the mean of its divisors is an integer number (2137044).

Almost surely, 2^80812809 is an apocalyptic number.

It is an amenable number.

80812809 is a deficient number, since it is larger than the sum of its proper divisors (73054359).

80812809 is a wasteful number, since it uses less digits than its factorization.

80812809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 80812809 is about 8989.5944847362. The cubic root of 80812809 is about 432.3413101313.

The spelling of 80812809 in words is "eighty million, eight hundred twelve thousand, eight hundred nine".