231866538 has 32 divisors (see below), whose sum is σ = 493646400. Its totient is φ = 72395136.

The previous prime is 231866507. The next prime is 231866543. The reversal of 231866538 is 835668132.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 231866538.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1281 + ... + 21572.

It is an arithmetic number, because the mean of its divisors is an integer number (15426450).

Almost surely, 2^231866538 is an apocalyptic number.

231866538 is an abundant number, since it is smaller than the sum of its proper divisors (261779862).

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

231866538 is a wasteful number, since it uses less digits than its factorization.

231866538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22966.

The product of its digits is 207360, while the sum is 42.

The square root of 231866538 is about 15227.1644766844. The cubic root of 231866538 is about 614.3455156543.

The spelling of 231866538 in words is "two hundred thirty-one million, eight hundred sixty-six thousand, five hundred thirty-eight".