206646161 has 4 divisors (see below), whose sum is σ = 207351732. Its totient is φ = 205940592.

The previous prime is 206646149. The next prime is 206646229. The reversal of 206646161 is 161646602.

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

It can be written as a sum of positive squares in 2 ways, for example, as 109327936 + 97318225 = 10456^2 + 9865^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206646161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206646131) 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, 352346 + ... + 352931.

It is an arithmetic number, because the mean of its divisors is an integer number (51837933).

Almost surely, 2^206646161 is an apocalyptic number.

It is an amenable number.

206646161 is a deficient number, since it is larger than the sum of its proper divisors (705571).

206646161 is an equidigital number, since it uses as much as digits as its factorization.

206646161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705570.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 206646161 is about 14375.1925552321. The cubic root of 206646161 is about 591.2109200660.

The spelling of 206646161 in words is "two hundred six million, six hundred forty-six thousand, one hundred sixty-one".