205106191 has 2 divisors, whose sum is σ = 205106192. Its totient is φ = 205106190.

The previous prime is 205106179. The next prime is 205106201. The reversal of 205106191 is 191601502.

205106191 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 is a cyclic number.

It is not a de Polignac number, because 205106191 - 2¹³ = 205097999 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205106101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102553095 + 102553096.

It is an arithmetic number, because the mean of its divisors is an integer number (102553096).

Almost surely, 2^205106191 is an apocalyptic number.

205106191 is a deficient number, since it is larger than the sum of its proper divisors (1).

205106191 is an equidigital number, since it uses as much as digits as its factorization.

205106191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 205106191 is about 14321.5289337417. The cubic root of 205106191 is about 589.7386480113.

Adding to 205106191 its reverse (191601502), we get a palindrome (396707693).

The spelling of 205106191 in words is "two hundred five million, one hundred six thousand, one hundred ninety-one".