812128027 has 4 divisors (see below), whose sum is σ = 813687336. Its totient is φ = 810568720.

The previous prime is 812128021. The next prime is 812128069. The reversal of 812128027 is 720821218.

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 812128027 - 2³ = 812128019 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 812128027.

It is not an unprimeable number, because it can be changed into a prime (812128021) 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 3 ways as a sum of consecutive naturals, for example, 778873 + ... + 779914.

It is an arithmetic number, because the mean of its divisors is an integer number (203421834).

Almost surely, 2^812128027 is an apocalyptic number.

812128027 is a deficient number, since it is larger than the sum of its proper divisors (1559309).

812128027 is a wasteful number, since it uses less digits than its factorization.

812128027 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1559308.

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 812128027 is about 28497.8600424663. The cubic root of 812128027 is about 932.9853681478.

The spelling of 812128027 in words is "eight hundred twelve million, one hundred twenty-eight thousand, twenty-seven".