206361661 has 4 divisors (see below), whose sum is σ = 225121824. Its totient is φ = 187601500.

The previous prime is 206361653. The next prime is 206361671. The reversal of 206361661 is 166163602.

206361661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 206361661 - 2³ = 206361653 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206361671) 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, 9380065 + ... + 9380086.

It is an arithmetic number, because the mean of its divisors is an integer number (56280456).

Almost surely, 2^206361661 is an apocalyptic number.

It is an amenable number.

206361661 is a deficient number, since it is larger than the sum of its proper divisors (18760163).

206361661 is a wasteful number, since it uses less digits than its factorization.

206361661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18760162.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 206361661 is about 14365.2936273506. The cubic root of 206361661 is about 590.9394790117.

The spelling of 206361661 in words is "two hundred six million, three hundred sixty-one thousand, six hundred sixty-one".