205056161 has 4 divisors (see below), whose sum is σ = 205085232. Its totient is φ = 205027092.

The previous prime is 205056143. The next prime is 205056169. The reversal of 205056161 is 161650502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 205056161 - 2¹⁴ = 205039777 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 205056161.

It is not an unprimeable number, because it can be changed into a prime (205056169) 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, 3530 + ... + 20556.

It is an arithmetic number, because the mean of its divisors is an integer number (51271308).

Almost surely, 2^205056161 is an apocalyptic number.

It is an amenable number.

205056161 is a deficient number, since it is larger than the sum of its proper divisors (29071).

205056161 is a wasteful number, since it uses less digits than its factorization.

205056161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29070.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 205056161 is about 14319.7821561642. The cubic root of 205056161 is about 589.6906939512.

The spelling of 205056161 in words is "two hundred five million, fifty-six thousand, one hundred sixty-one".