231645 has 8 divisors (see below), whose sum is σ = 370656. Its totient is φ = 123536.

The previous prime is 231643. The next prime is 231661. The reversal of 231645 is 546132.

It is a happy number.

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 231645 - 2¹ = 231643 is a prime.

It is a Curzon number.

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 (231643) 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, 7707 + ... + 7736.

It is an arithmetic number, because the mean of its divisors is an integer number (46332).

2²³¹⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

231645 is a deficient number, since it is larger than the sum of its proper divisors (139011).

231645 is a wasteful number, since it uses less digits than its factorization.

231645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15451.

The product of its digits is 720, while the sum is 21.

The square root of 231645 is about 481.2951277543. The cubic root of 231645 is about 61.4149793513.

Adding to 231645 its reverse (546132), we get a palindrome (777777).

The spelling of 231645 in words is "two hundred thirty-one thousand, six hundred forty-five".