204985687 has 6 divisors (see below), whose sum is σ = 209865552. Its totient is φ = 200216772.

The previous prime is 204985667. The next prime is 204985709. The reversal of 204985687 is 786589402.

It is not a de Polignac number, because 204985687 - 2¹⁵ = 204952919 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 204985687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204985607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 53583 + ... + 57280.

It is an arithmetic number, because the mean of its divisors is an integer number (34977592).

Almost surely, 2^204985687 is an apocalyptic number.

204985687 is a deficient number, since it is larger than the sum of its proper divisors (4879865).

204985687 is an equidigital number, since it uses as much as digits as its factorization.

204985687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110949 (or 110906 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 49.

The square root of 204985687 is about 14317.3212229104. The cubic root of 204985687 is about 589.6231309585.

The spelling of 204985687 in words is "two hundred four million, nine hundred eighty-five thousand, six hundred eighty-seven".