204637802897861 has 2 divisors, whose sum is σ = 204637802897862. Its totient is φ = 204637802897860.

The previous prime is 204637802897851. The next prime is 204637802897893. The reversal of 204637802897861 is 168798208736402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 132586243452100 + 72051559445761 = 11514610^2 + 8488319^2 .

It is a cyclic number.

It is not a de Polignac number, because 204637802897861 - 2³⁰ = 204636729156037 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204637802897831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102318901448930 + 102318901448931.

It is an arithmetic number, because the mean of its divisors is an integer number (102318901448931).

Almost surely, 2^{204637802897861} is an apocalyptic number.

It is an amenable number.

204637802897861 is a deficient number, since it is larger than the sum of its proper divisors (1).

204637802897861 is an equidigital number, since it uses as much as digits as its factorization.

204637802897861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 390168576, while the sum is 71.

The spelling of 204637802897861 in words is "two hundred four trillion, six hundred thirty-seven billion, eight hundred two million, eight hundred ninety-seven thousand, eight hundred sixty-one".