206551 has 2 divisors, whose sum is σ = 206552. Its totient is φ = 206550.

The previous prime is 206543. The next prime is 206593. The reversal of 206551 is 155602.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 206551 - 2³ = 206543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103275 + 103276.

It is an arithmetic number, because the mean of its divisors is an integer number (103276).

2²⁰⁶⁵⁵¹ is an apocalyptic number.

206551 is a deficient number, since it is larger than the sum of its proper divisors (1).

206551 is an equidigital number, since it uses as much as digits as its factorization.

206551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 206551 is about 454.4788223889. The cubic root of 206551 is about 59.1120154833.

It can be divided in two parts, 2065 and 51, that added together give a square (2116 = 46²).

The spelling of 206551 in words is "two hundred six thousand, five hundred fifty-one".