204864471657 has 24 divisors (see below), whose sum is σ = 297038241864. Its totient is φ = 136058413824.

The previous prime is 204864471631. The next prime is 204864471667. The reversal of 204864471657 is 756174468402.

204864471657 is a `hidden beast` number, since 2 + 0 + 486 + 44 + 71 + 6 + 57 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 197957365776 + 6907105881 = 444924^2 + 83109^2 .

It is not a de Polignac number, because 204864471657 - 2¹⁰ = 204864470633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (204864471667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7678813 + ... + 7705445.

It is an arithmetic number, because the mean of its divisors is an integer number (12376593411).

Almost surely, 2^204864471657 is an apocalyptic number.

It is an amenable number.

204864471657 is a deficient number, since it is larger than the sum of its proper divisors (92173770207).

204864471657 is a wasteful number, since it uses less digits than its factorization.

204864471657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29849 (or 29846 counting only the distinct ones).

The product of its (nonzero) digits is 9031680, while the sum is 54.

The spelling of 204864471657 in words is "two hundred four billion, eight hundred sixty-four million, four hundred seventy-one thousand, six hundred fifty-seven".