206891 has 4 divisors (see below), whose sum is σ = 217800. Its totient is φ = 195984.

The previous prime is 206887. The next prime is 206897. The reversal of 206891 is 198602.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 206891 - 2² = 206887 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 206891.

It is not an unprimeable number, because it can be changed into a prime (206897) 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, 5426 + ... + 5463.

It is an arithmetic number, because the mean of its divisors is an integer number (54450).

2²⁰⁶⁸⁹¹ is an apocalyptic number.

206891 is a deficient number, since it is larger than the sum of its proper divisors (10909).

206891 is a wasteful number, since it uses less digits than its factorization.

206891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10908.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 206891 is about 454.8527234172. The cubic root of 206891 is about 59.1444321224.

The spelling of 206891 in words is "two hundred six thousand, eight hundred ninety-one".