205773121 has 4 divisors (see below), whose sum is σ = 205820100. Its totient is φ = 205726144.

The previous prime is 205773109. The next prime is 205773167. The reversal of 205773121 is 121377502.

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 184280625 + 21492496 = 13575^2 + 4636^2 .

It is a cyclic number.

It is not a de Polignac number, because 205773121 - 2⁵ = 205773089 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 205773121.

It is not an unprimeable number, because it can be changed into a prime (205773221) 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, 16156 + ... + 25933.

It is an arithmetic number, because the mean of its divisors is an integer number (51455025).

Almost surely, 2^205773121 is an apocalyptic number.

It is an amenable number.

205773121 is a deficient number, since it is larger than the sum of its proper divisors (46979).

205773121 is an equidigital number, since it uses as much as digits as its factorization.

205773121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46978.

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 205773121 is about 14344.7942125358. The cubic root of 205773121 is about 590.3771609338.

The spelling of 205773121 in words is "two hundred five million, seven hundred seventy-three thousand, one hundred twenty-one".