231997539 has 8 divisors (see below), whose sum is σ = 310625280. Its totient is φ = 154017416.

The previous prime is 231997537. The next prime is 231997559. The reversal of 231997539 is 935799132.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 231997539 - 2¹ = 231997537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231997531) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 161067 + ... + 162500.

It is an arithmetic number, because the mean of its divisors is an integer number (38828160).

Almost surely, 2^231997539 is an apocalyptic number.

231997539 is a deficient number, since it is larger than the sum of its proper divisors (78627741).

231997539 is a wasteful number, since it uses less digits than its factorization.

231997539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323809.

The product of its digits is 459270, while the sum is 48.

The square root of 231997539 is about 15231.4654252308. The cubic root of 231997539 is about 614.4611924365.

The spelling of 231997539 in words is "two hundred thirty-one million, nine hundred ninety-seven thousand, five hundred thirty-nine".