206580249121 has 9 divisors (see below), whose sum is σ = 210050518899. Its totient is φ = 203166417000.

The previous prime is 206580249119. The next prime is 206580249133. The reversal of 206580249121 is 121942085602.

It is a happy number.

The square root of 206580249121 is 454511.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 6717605521 + 199862643600 = 81961^2 + 447060^2 .

It is not a de Polignac number, because 206580249121 - 2¹ = 206580249119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206580249181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 27721446 + ... + 27728896.

Almost surely, 2^206580249121 is an apocalyptic number.

206580249121 is the 454511-st square number.

206580249121 is the 227256-th centered octagonal number.

It is an amenable number.

206580249121 is a deficient number, since it is larger than the sum of its proper divisors (3470269778).

206580249121 is an frugal number, since it uses more digits than its factorization.

206580249121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15024 (or 7512 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The spelling of 206580249121 in words is "two hundred six billion, five hundred eighty million, two hundred forty-nine thousand, one hundred twenty-one".