812001889 has 16 divisors (see below), whose sum is σ = 887621328. Its totient is φ = 739694592.

The previous prime is 812001887. The next prime is 812001899. The reversal of 812001889 is 988100218.

It can be written as a sum of positive squares in 8 ways, for example, as 270043489 + 541958400 = 16433^2 + 23280^2 .

It is a cyclic number.

It is not a de Polignac number, because 812001889 - 2¹ = 812001887 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (812001881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120637 + ... + 127189.

It is an arithmetic number, because the mean of its divisors is an integer number (55476333).

Almost surely, 2^812001889 is an apocalyptic number.

It is an amenable number.

812001889 is a deficient number, since it is larger than the sum of its proper divisors (75619439).

812001889 is a wasteful number, since it uses less digits than its factorization.

812001889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6804.

The product of its (nonzero) digits is 9216, while the sum is 37.

The square root of 812001889 is about 28495.6468429829. The cubic root of 812001889 is about 932.9370625449.

The spelling of 812001889 in words is "eight hundred twelve million, one thousand, eight hundred eighty-nine".