206353775261 has 2 divisors, whose sum is σ = 206353775262. Its totient is φ = 206353775260.

The previous prime is 206353775197. The next prime is 206353775263. The reversal of 206353775261 is 162577353602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 142124476036 + 64229299225 = 376994^2 + 253435^2 .

It is a cyclic number.

It is not a de Polignac number, because 206353775261 - 2⁶ = 206353775197 is a prime.

Together with 206353775263, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206353775263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103176887630 + 103176887631.

It is an arithmetic number, because the mean of its divisors is an integer number (103176887631).

Almost surely, 2^206353775261 is an apocalyptic number.

It is an amenable number.

206353775261 is a deficient number, since it is larger than the sum of its proper divisors (1).

206353775261 is an equidigital number, since it uses as much as digits as its factorization.

206353775261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1587600, while the sum is 47.

The spelling of 206353775261 in words is "two hundred six billion, three hundred fifty-three million, seven hundred seventy-five thousand, two hundred sixty-one".