204856857 has 10 divisors (see below), whose sum is σ = 306020858. Its totient is φ = 136571184.

The previous prime is 204856853. The next prime is 204856867. The reversal of 204856857 is 758658402.

It can be written as a sum of positive squares in only one way, i.e., 193098816 + 11758041 = 13896^2 + 3429^2 .

It is not a de Polignac number, because 204856857 - 2² = 204856853 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (204856853) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1264468 + ... + 1264629.

Almost surely, 2^204856857 is an apocalyptic number.

204856857 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

204856857 is a deficient number, since it is larger than the sum of its proper divisors (101164001).

204856857 is an equidigital number, since it uses as much as digits as its factorization.

204856857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2529109 (or 2529100 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 45.

The square root of 204856857 is about 14312.8214199717. The cubic root of 204856857 is about 589.4995823861.

The spelling of 204856857 in words is "two hundred four million, eight hundred fifty-six thousand, eight hundred fifty-seven".