206820 has 48 divisors (see below), whose sum is σ = 645120. Its totient is φ = 55008.

The previous prime is 206819. The next prime is 206821. The reversal of 206820 is 28602.

It is an interprime number because it is at equal distance from previous prime (206819) and next prime (206821).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 206793 and 206802.

It is not an unprimeable number, because it can be changed into a prime (206821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 349 + ... + 731.

It is an arithmetic number, because the mean of its divisors is an integer number (13440).

2²⁰⁶⁸²⁰ is an apocalyptic number.

206820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 206820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322560).

206820 is an abundant number, since it is smaller than the sum of its proper divisors (438300).

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

206820 is a wasteful number, since it uses less digits than its factorization.

206820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401 (or 393 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 206820 is about 454.7746694793. The cubic root of 206820 is about 59.1376657009.

The spelling of 206820 in words is "two hundred six thousand, eight hundred twenty".