811988 has 12 divisors (see below), whose sum is σ = 1504692. Its totient is φ = 382080.

The previous prime is 811981. The next prime is 811991. The reversal of 811988 is 889118.

811988 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 425104 + 386884 = 652^2 + 622^2 .

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (811981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5903 + ... + 6038.

It is an arithmetic number, because the mean of its divisors is an integer number (125391).

2⁸¹¹⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

811988 is a deficient number, since it is larger than the sum of its proper divisors (692704).

811988 is a wasteful number, since it uses less digits than its factorization.

811988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11962 (or 11960 counting only the distinct ones).

The product of its digits is 4608, while the sum is 35.

The square root of 811988 is about 901.1037676095. The cubic root of 811988 is about 93.2931743330.

It can be divided in two parts, 81 and 1988, that multiplied together give a triangular number (161028 = T₅₆₇).

The spelling of 811988 in words is "eight hundred eleven thousand, nine hundred eighty-eight".