205025343989 has 2 divisors, whose sum is σ = 205025343990. Its totient is φ = 205025343988.

The previous prime is 205025343923. The next prime is 205025344003. The reversal of 205025343989 is 989343520502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 205000672900 + 24671089 = 452770^2 + 4967^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205025343989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205025343889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102512671994 + 102512671995.

It is an arithmetic number, because the mean of its divisors is an integer number (102512671995).

Almost surely, 2^205025343989 is an apocalyptic number.

It is an amenable number.

205025343989 is a deficient number, since it is larger than the sum of its proper divisors (1).

205025343989 is an equidigital number, since it uses as much as digits as its factorization.

205025343989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2332800, while the sum is 50.

The spelling of 205025343989 in words is "two hundred five billion, twenty-five million, three hundred forty-three thousand, nine hundred eighty-nine".