205801 has 4 divisors (see below), whose sum is σ = 207504. Its totient is φ = 204100.

The previous prime is 205783. The next prime is 205817. The reversal of 205801 is 108502.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 108502 = 2 ⋅54251.

It is a cyclic number.

It is not a de Polignac number, because 205801 - 2¹³ = 197609 is a prime.

205801 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (205201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 655 + ... + 916.

It is an arithmetic number, because the mean of its divisors is an integer number (51876).

2²⁰⁵⁸⁰¹ is an apocalyptic number.

It is an amenable number.

205801 is a deficient number, since it is larger than the sum of its proper divisors (1703).

205801 is a wasteful number, since it uses less digits than its factorization.

205801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1702.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 205801 is about 453.6529510540. The cubic root of 205801 is about 59.0403821983.

The spelling of 205801 in words is "two hundred five thousand, eight hundred one".