231812928 has 140 divisors (see below), whose sum is σ = 695756292. Its totient is φ = 76308480.

The previous prime is 231812927. The next prime is 231813011. The reversal of 231812928 is 829218132.

It can be written as a sum of positive squares in 2 ways, for example, as 88962624 + 142850304 = 9432^2 + 11952^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 231812892 and 231812901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231812927) 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 19 ways as a sum of consecutive naturals, for example, 502618 + ... + 503078.

Almost surely, 2^231812928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231812928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (347878146).

231812928 is an abundant number, since it is smaller than the sum of its proper divisors (463943364).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

231812928 is an equidigital number, since it uses as much as digits as its factorization.

231812928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582 (or 563 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 231812928 is about 15225.4040340478. The cubic root of 231812928 is about 614.2981642742.

The spelling of 231812928 in words is "two hundred thirty-one million, eight hundred twelve thousand, nine hundred twenty-eight".