208944922561 has 2 divisors, whose sum is σ = 208944922562. Its totient is φ = 208944922560.

The previous prime is 208944922513. The next prime is 208944922577. The reversal of 208944922561 is 165229449802.

208944922561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 163199840400 + 45745082161 = 403980^2 + 213881^2 .

It is a cyclic number.

It is not a de Polignac number, because 208944922561 - 2¹⁵ = 208944889793 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 208944922499 and 208944922508.

It is not a weakly prime, because it can be changed into another prime (208944925561) 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, 104472461280 + 104472461281.

It is an arithmetic number, because the mean of its divisors is an integer number (104472461281).

Almost surely, 2^208944922561 is an apocalyptic number.

It is an amenable number.

208944922561 is a deficient number, since it is larger than the sum of its proper divisors (1).

208944922561 is an equidigital number, since it uses as much as digits as its factorization.

208944922561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2488320, while the sum is 52.

The spelling of 208944922561 in words is "two hundred eight billion, nine hundred forty-four million, nine hundred twenty-two thousand, five hundred sixty-one".