31845 has 16 divisors (see below), whose sum is σ = 55872. Its totient is φ = 15360.

The previous prime is 31817. The next prime is 31847. The reversal of 31845 is 54813.

It is not a de Polignac number, because 31845 - 2⁹ = 31333 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31847) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69 + ... + 261.

It is an arithmetic number, because the mean of its divisors is an integer number (3492).

2³¹⁸⁴⁵ is an apocalyptic number.

It is an amenable number.

31845 is a deficient number, since it is larger than the sum of its proper divisors (24027).

31845 is a wasteful number, since it uses less digits than its factorization.

31845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212.

The product of its digits is 480, while the sum is 21.

The square root of 31845 is about 178.4516741306. The cubic root of 31845 is about 31.6966782270.

It can be divided in two parts, 318 and 45, that added together give a palindrome (363).

The spelling of 31845 in words is "thirty-one thousand, eight hundred forty-five".