205015807889 has 2 divisors, whose sum is σ = 205015807890. Its totient is φ = 205015807888.

The previous prime is 205015807883. The next prime is 205015807891. The reversal of 205015807889 is 988708510502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 110102521489 + 94913286400 = 331817^2 + 308080^2 .

It is a cyclic number.

It is not a de Polignac number, because 205015807889 - 2⁴ = 205015807873 is a prime.

Together with 205015807891, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205015807889.

It is not a weakly prime, because it can be changed into another prime (205015807883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102507903944 + 102507903945.

It is an arithmetic number, because the mean of its divisors is an integer number (102507903945).

Almost surely, 2^205015807889 is an apocalyptic number.

It is an amenable number.

205015807889 is a deficient number, since it is larger than the sum of its proper divisors (1).

205015807889 is an equidigital number, since it uses as much as digits as its factorization.

205015807889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1612800, while the sum is 53.

The spelling of 205015807889 in words is "two hundred five billion, fifteen million, eight hundred seven thousand, eight hundred eighty-nine".