812928561 has 8 divisors (see below), whose sum is σ = 1085552160. Its totient is φ = 541128672.

The previous prime is 812928553. The next prime is 812928617. The reversal of 812928561 is 165829218.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 812928561 - 2³ = 812928553 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (812928161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 203620 + ... + 207573.

It is an arithmetic number, because the mean of its divisors is an integer number (135694020).

Almost surely, 2^812928561 is an apocalyptic number.

It is an amenable number.

812928561 is a deficient number, since it is larger than the sum of its proper divisors (272623599).

812928561 is a wasteful number, since it uses less digits than its factorization.

812928561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411855.

The product of its digits is 69120, while the sum is 42.

The square root of 812928561 is about 28511.9020936871. The cubic root of 812928561 is about 933.2918227995.

The spelling of 812928561 in words is "eight hundred twelve million, nine hundred twenty-eight thousand, five hundred sixty-one".