231566 has 4 divisors (see below), whose sum is σ = 347352. Its totient is φ = 115782.

The previous prime is 231563. The next prime is 231571. The reversal of 231566 is 665132.

It is a semiprime because it is the product of two primes.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57890 + ... + 57893.

It is an arithmetic number, because the mean of its divisors is an integer number (86838).

2²³¹⁵⁶⁶ is an apocalyptic number.

231566 is a deficient number, since it is larger than the sum of its proper divisors (115786).

231566 is a wasteful number, since it uses less digits than its factorization.

231566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115785.

The product of its digits is 1080, while the sum is 23.

The square root of 231566 is about 481.2130505296. The cubic root of 231566 is about 61.4079969213.

Adding to 231566 its reverse (665132), we get a palindrome (896698).

It can be divided in two parts, 231 and 566, that added together give a palindrome (797).

The spelling of 231566 in words is "two hundred thirty-one thousand, five hundred sixty-six".