205731 has 6 divisors (see below), whose sum is σ = 297180. Its totient is φ = 137148.

The previous prime is 205721. The next prime is 205759. The reversal of 205731 is 137502.

205731 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 205731 - 2⁷ = 205603 is a prime.

It is a super-2 number, since 2×205731² = 84650488722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (205721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11421 + ... + 11438.

It is an arithmetic number, because the mean of its divisors is an integer number (49530).

2²⁰⁵⁷³¹ is an apocalyptic number.

205731 is a deficient number, since it is larger than the sum of its proper divisors (91449).

205731 is a wasteful number, since it uses less digits than its factorization.

205731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22865 (or 22862 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 18.

The square root of 205731 is about 453.5757930049. The cubic root of 205731 is about 59.0336875508.

The spelling of 205731 in words is "two hundred five thousand, seven hundred thirty-one".