206778 has 32 divisors (see below), whose sum is σ = 487872. Its totient is φ = 57600.

The previous prime is 206749. The next prime is 206779. The reversal of 206778 is 877602.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206779) 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 in 15 ways as a sum of consecutive naturals, for example, 738 + ... + 978.

It is an arithmetic number, because the mean of its divisors is an integer number (15246).

2²⁰⁶⁷⁷⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 206778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243936).

206778 is an abundant number, since it is smaller than the sum of its proper divisors (281094).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

206778 is a wasteful number, since it uses less digits than its factorization.

206778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270.

The product of its (nonzero) digits is 4704, while the sum is 30.

The square root of 206778 is about 454.7284904204. The cubic root of 206778 is about 59.1336623000.

It can be divided in two parts, 2067 and 78, that added together give a triangular number (2145 = T₆₅).

The spelling of 206778 in words is "two hundred six thousand, seven hundred seventy-eight".