812928509 has 16 divisors (see below), whose sum is σ = 863311680. Its totient is φ = 763344000.

The previous prime is 812928503. The next prime is 812928527. The reversal of 812928509 is 905829218.

It is not a de Polignac number, because 812928509 - 2²⁰ = 811879933 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 812928509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812928503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1778609 + ... + 1779065.

It is an arithmetic number, because the mean of its divisors is an integer number (53956980).

Almost surely, 2^812928509 is an apocalyptic number.

It is an amenable number.

812928509 is a deficient number, since it is larger than the sum of its proper divisors (50383171).

812928509 is a wasteful number, since it uses less digits than its factorization.

812928509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1100.

The product of its (nonzero) digits is 103680, while the sum is 44.

The square root of 812928509 is about 28511.9011817872. The cubic root of 812928509 is about 933.2918028998.

The spelling of 812928509 in words is "eight hundred twelve million, nine hundred twenty-eight thousand, five hundred nine".