205968121 has 4 divisors (see below), whose sum is σ = 213070500. Its totient is φ = 198865744.

The previous prime is 205968083. The next prime is 205968127. The reversal of 205968121 is 121869502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 80281600 + 125686521 = 8960^2 + 11211^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205968121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205968127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3551146 + ... + 3551203.

It is an arithmetic number, because the mean of its divisors is an integer number (53267625).

Almost surely, 2^205968121 is an apocalyptic number.

It is an amenable number.

205968121 is a deficient number, since it is larger than the sum of its proper divisors (7102379).

205968121 is an equidigital number, since it uses as much as digits as its factorization.

205968121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7102378.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 205968121 is about 14351.5894938505. The cubic root of 205968121 is about 590.5635915028.

The spelling of 205968121 in words is "two hundred five million, nine hundred sixty-eight thousand, one hundred twenty-one".