231931836 has 72 divisors (see below), whose sum is σ = 624514800. Its totient is φ = 75209472.

The previous prime is 231931831. The next prime is 231931837. The reversal of 231931836 is 638139132.

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

It is a self number, because there is not a number n which added to its sum of digits gives 231931836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231931831) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32740 + ... + 39188.

Almost surely, 2^231931836 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 231931836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312257400).

231931836 is an abundant number, since it is smaller than the sum of its proper divisors (392582964).

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

231931836 is a wasteful number, since it uses less digits than its factorization.

231931836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6505 (or 6491 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 231931836 is about 15229.3084544243. The cubic root of 231931836 is about 614.4031806781.

The spelling of 231931836 in words is "two hundred thirty-one million, nine hundred thirty-one thousand, eight hundred thirty-six".