205355105489 has 2 divisors, whose sum is σ = 205355105490. Its totient is φ = 205355105488.

The previous prime is 205355105477. The next prime is 205355105503. The reversal of 205355105489 is 984501553502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146548855489 + 58806250000 = 382817^2 + 242500^2 .

It is a cyclic number.

It is not a de Polignac number, because 205355105489 - 2⁸ = 205355105233 is a prime.

It is not a weakly prime, because it can be changed into another prime (205355105419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102677552744 + 102677552745.

It is an arithmetic number, because the mean of its divisors is an integer number (102677552745).

Almost surely, 2^205355105489 is an apocalyptic number.

It is an amenable number.

205355105489 is a deficient number, since it is larger than the sum of its proper divisors (1).

205355105489 is an equidigital number, since it uses as much as digits as its factorization.

205355105489 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080000, while the sum is 47.

The spelling of 205355105489 in words is "two hundred five billion, three hundred fifty-five million, one hundred five thousand, four hundred eighty-nine".