205642671 has 16 divisors (see below), whose sum is σ = 300289920. Its totient is φ = 124403040.

The previous prime is 205642667. The next prime is 205642691. The reversal of 205642671 is 176246502.

It is not a de Polignac number, because 205642671 - 2² = 205642667 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205642601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42385 + ... + 46986.

It is an arithmetic number, because the mean of its divisors is an integer number (18768120).

Almost surely, 2^205642671 is an apocalyptic number.

205642671 is a deficient number, since it is larger than the sum of its proper divisors (94647249).

205642671 is a wasteful number, since it uses less digits than its factorization.

205642671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89446.

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 205642671 is about 14340.2465459977. The cubic root of 205642671 is about 590.2523779034.

The spelling of 205642671 in words is "two hundred five million, six hundred forty-two thousand, six hundred seventy-one".