205646641 has 2 divisors, whose sum is σ = 205646642. Its totient is φ = 205646640.

The previous prime is 205646599. The next prime is 205646663. The reversal of 205646641 is 146646502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 113870241 + 91776400 = 10671^2 + 9580^2 .

It is a cyclic number.

It is not a de Polignac number, because 205646641 - 2⁷ = 205646513 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 205646597 and 205646606.

It is not a weakly prime, because it can be changed into another prime (205646681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102823320 + 102823321.

It is an arithmetic number, because the mean of its divisors is an integer number (102823321).

Almost surely, 2^205646641 is an apocalyptic number.

It is an amenable number.

205646641 is a deficient number, since it is larger than the sum of its proper divisors (1).

205646641 is an equidigital number, since it uses as much as digits as its factorization.

205646641 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 205646641 is about 14340.3849669386. The cubic root of 205646641 is about 590.2561762182.

The spelling of 205646641 in words is "two hundred five million, six hundred forty-six thousand, six hundred forty-one".