231687 has 8 divisors (see below), whose sum is σ = 343280. Its totient is φ = 154440.

The previous prime is 231677. The next prime is 231701. The reversal of 231687 is 786132.

231687 is nontrivially palindromic in base 8.

It is not a de Polignac number, because 231687 - 2⁷ = 231559 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 8581 = 231687 / (2 + 3 + 1 + 6 + 8 + 7).

It is a Duffinian number.

231687 is a lucky number.

It is a plaindrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 231687.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 231687.

It is not an unprimeable number, because it can be changed into a prime (231607) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4264 + ... + 4317.

It is an arithmetic number, because the mean of its divisors is an integer number (42910).

2²³¹⁶⁸⁷ is an apocalyptic number.

231687 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

231687 is a deficient number, since it is larger than the sum of its proper divisors (111593).

231687 is an equidigital number, since it uses as much as digits as its factorization.

231687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8590 (or 8584 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 231687 is about 481.3387580488. The cubic root of 231687 is about 61.4186908830.

The spelling of 231687 in words is "two hundred thirty-one thousand, six hundred eighty-seven".