205975109 has 2 divisors, whose sum is σ = 205975110. Its totient is φ = 205975108.

The previous prime is 205975087. The next prime is 205975127. The reversal of 205975109 is 901579502.

205975109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165842884 + 40132225 = 12878^2 + 6335^2 .

It is a cyclic number.

It is not a de Polignac number, because 205975109 - 2¹⁶ = 205909573 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205975169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102987554 + 102987555.

It is an arithmetic number, because the mean of its divisors is an integer number (102987555).

Almost surely, 2^205975109 is an apocalyptic number.

It is an amenable number.

205975109 is a deficient number, since it is larger than the sum of its proper divisors (1).

205975109 is an equidigital number, since it uses as much as digits as its factorization.

205975109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28350, while the sum is 38.

The square root of 205975109 is about 14351.8329491393. The cubic root of 205975109 is about 590.5702702252.

The spelling of 205975109 in words is "two hundred five million, nine hundred seventy-five thousand, one hundred nine".