811231889 has 4 divisors (see below), whose sum is σ = 873634356. Its totient is φ = 748829424.

The previous prime is 811231867. The next prime is 811231921. The reversal of 811231889 is 988132118.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 50410000 + 760821889 = 7100^2 + 27583^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-811231889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (811231829) 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, 31201214 + ... + 31201239.

It is an arithmetic number, because the mean of its divisors is an integer number (218408589).

Almost surely, 2^811231889 is an apocalyptic number.

It is an amenable number.

811231889 is a deficient number, since it is larger than the sum of its proper divisors (62402467).

811231889 is a wasteful number, since it uses less digits than its factorization.

811231889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62402466.

The product of its digits is 27648, while the sum is 41.

The square root of 811231889 is about 28482.1328028643. The cubic root of 811231889 is about 932.6420760696.

The spelling of 811231889 in words is "eight hundred eleven million, two hundred thirty-one thousand, eight hundred eighty-nine".