205680017 has 8 divisors (see below), whose sum is σ = 209822976. Its totient is φ = 201568752.

The previous prime is 205679993. The next prime is 205680019. The reversal of 205680017 is 710086502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 205680017 - 2⁶ = 205679953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205680019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5408 + ... + 20990.

It is an arithmetic number, because the mean of its divisors is an integer number (26227872).

Almost surely, 2^205680017 is an apocalyptic number.

It is an amenable number.

205680017 is a deficient number, since it is larger than the sum of its proper divisors (4142959).

205680017 is a wasteful number, since it uses less digits than its factorization.

205680017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15847.

The product of its (nonzero) digits is 3360, while the sum is 29.

The square root of 205680017 is about 14341.5486262816. The cubic root of 205680017 is about 590.2881069196.

The spelling of 205680017 in words is "two hundred five million, six hundred eighty thousand, seventeen".