205997 has 8 divisors (see below), whose sum is σ = 229152. Its totient is φ = 183600.

The previous prime is 205993. The next prime is 206009. The reversal of 205997 is 799502.

205997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 205997 - 2² = 205993 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205991) 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, 518 + ... + 824.

It is an arithmetic number, because the mean of its divisors is an integer number (28644).

2²⁰⁵⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

205997 is a deficient number, since it is larger than the sum of its proper divisors (23155).

205997 is a wasteful number, since it uses less digits than its factorization.

205997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379.

The product of its (nonzero) digits is 5670, while the sum is 32.

The square root of 205997 is about 453.8689238095. The cubic root of 205997 is about 59.0591191387.

Subtracting 205997 from its reverse (799502), we obtain a triangular number (593505 = T₁₀₈₉).

The spelling of 205997 in words is "two hundred five thousand, nine hundred ninety-seven".