205851264089 has 2 divisors, whose sum is σ = 205851264090. Its totient is φ = 205851264088.

The previous prime is 205851264077. The next prime is 205851264127. The reversal of 205851264089 is 980462158502.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 194363711689 + 11487552400 = 440867^2 + 107180^2 .

It is a cyclic number.

It is not a de Polignac number, because 205851264089 - 2²⁰ = 205850215513 is a prime.

It is not a weakly prime, because it can be changed into another prime (205851204089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102925632044 + 102925632045.

It is an arithmetic number, because the mean of its divisors is an integer number (102925632045).

Almost surely, 2^205851264089 is an apocalyptic number.

It is an amenable number.

205851264089 is a deficient number, since it is larger than the sum of its proper divisors (1).

205851264089 is an equidigital number, since it uses as much as digits as its factorization.

205851264089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1382400, while the sum is 50.

The spelling of 205851264089 in words is "two hundred five billion, eight hundred fifty-one million, two hundred sixty-four thousand, eighty-nine".