205993 has 2 divisors, whose sum is σ = 205994. Its totient is φ = 205992.

The previous prime is 205991. The next prime is 206009. The reversal of 205993 is 399502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 205209 + 784 = 453^2 + 28^2 .

It is a cyclic number.

It is not a de Polignac number, because 205993 - 2¹ = 205991 is a prime.

Together with 205991, it forms a pair of twin primes.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (205991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102996 + 102997.

It is an arithmetic number, because the mean of its divisors is an integer number (102997).

2²⁰⁵⁹⁹³ is an apocalyptic number.

It is an amenable number.

205993 is a deficient number, since it is larger than the sum of its proper divisors (1).

205993 is an equidigital number, since it uses as much as digits as its factorization.

205993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2430, while the sum is 28.

The square root of 205993 is about 453.8645172295. The cubic root of 205993 is about 59.0587368710.

It can be divided in two parts, 20599 and 3, that added together give a palindrome (20602).

The spelling of 205993 in words is "two hundred five thousand, nine hundred ninety-three".