206591 has 8 divisors (see below), whose sum is σ = 257664. Its totient is φ = 160920.

The previous prime is 206551. The next prime is 206593. The reversal of 206591 is 195602.

206591 = 89² + 90² + ... + 109².

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 206591 - 2⁶ = 206527 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1265 + ... + 1418.

It is an arithmetic number, because the mean of its divisors is an integer number (32208).

2²⁰⁶⁵⁹¹ is an apocalyptic number.

206591 is a deficient number, since it is larger than the sum of its proper divisors (51073).

206591 is a wasteful number, since it uses less digits than its factorization.

206591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2701.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 206591 is about 454.5228267095. The cubic root of 206591 is about 59.1158310511.

It can be divided in two parts, 206 and 591, that added together give a palindrome (797).

The spelling of 206591 in words is "two hundred six thousand, five hundred ninety-one".