206273967521 has 2 divisors, whose sum is σ = 206273967522. Its totient is φ = 206273967520.

The previous prime is 206273967479. The next prime is 206273967541. The reversal of 206273967521 is 125769372602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 133856466496 + 72417501025 = 365864^2 + 269105^2 .

It is a cyclic number.

It is not a de Polignac number, because 206273967521 - 2³⁰ = 205200225697 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 206273967521.

It is not a weakly prime, because it can be changed into another prime (206273967541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103136983760 + 103136983761.

It is an arithmetic number, because the mean of its divisors is an integer number (103136983761).

Almost surely, 2^206273967521 is an apocalyptic number.

It is an amenable number.

206273967521 is a deficient number, since it is larger than the sum of its proper divisors (1).

206273967521 is an equidigital number, since it uses as much as digits as its factorization.

206273967521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1905120, while the sum is 50.

The spelling of 206273967521 in words is "two hundred six billion, two hundred seventy-three million, nine hundred sixty-seven thousand, five hundred twenty-one".