206036513621 has 2 divisors, whose sum is σ = 206036513622. Its totient is φ = 206036513620.

The previous prime is 206036513569. The next prime is 206036513677. The reversal of 206036513621 is 126315630602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122090143396 + 83946370225 = 349414^2 + 289735^2 .

It is a cyclic number.

It is not a de Polignac number, because 206036513621 - 2¹⁰ = 206036512597 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206036513021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103018256810 + 103018256811.

It is an arithmetic number, because the mean of its divisors is an integer number (103018256811).

Almost surely, 2^206036513621 is an apocalyptic number.

It is an amenable number.

206036513621 is a deficient number, since it is larger than the sum of its proper divisors (1).

206036513621 is an equidigital number, since it uses as much as digits as its factorization.

206036513621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 35.

The spelling of 206036513621 in words is "two hundred six billion, thirty-six million, five hundred thirteen thousand, six hundred twenty-one".