206556606491 has 2 divisors, whose sum is σ = 206556606492. Its totient is φ = 206556606490.

The previous prime is 206556606481. The next prime is 206556606527. The reversal of 206556606491 is 194606655602.

206556606491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206556606491 is a prime.

It is not a weakly prime, because it can be changed into another prime (206556606481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103278303245 + 103278303246.

It is an arithmetic number, because the mean of its divisors is an integer number (103278303246).

Almost surely, 2^206556606491 is an apocalyptic number.

206556606491 is a deficient number, since it is larger than the sum of its proper divisors (1).

206556606491 is an equidigital number, since it uses as much as digits as its factorization.

206556606491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2332800, while the sum is 50.

The spelling of 206556606491 in words is "two hundred six billion, five hundred fifty-six million, six hundred six thousand, four hundred ninety-one".