205172985 has 8 divisors (see below), whose sum is σ = 328276800. Its totient is φ = 109425584.

The previous prime is 205172969. The next prime is 205173011. The reversal of 205172985 is 589271502.

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 205172985 - 2⁴ = 205172969 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6839085 + ... + 6839114.

It is an arithmetic number, because the mean of its divisors is an integer number (41034600).

Almost surely, 2^205172985 is an apocalyptic number.

It is an amenable number.

205172985 is a deficient number, since it is larger than the sum of its proper divisors (123103815).

205172985 is a wasteful number, since it uses less digits than its factorization.

205172985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13678207.

The product of its (nonzero) digits is 50400, while the sum is 39.

The square root of 205172985 is about 14323.8606876777. The cubic root of 205172985 is about 589.8026583140.

The spelling of 205172985 in words is "two hundred five million, one hundred seventy-two thousand, nine hundred eighty-five".