205289291 has 2 divisors, whose sum is σ = 205289292. Its totient is φ = 205289290.

The previous prime is 205289219. The next prime is 205289303. The reversal of 205289291 is 192982502.

Together with previous prime (205289219) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205289291 is a prime.

It is not a weakly prime, because it can be changed into another prime (205229291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102644645 + 102644646.

It is an arithmetic number, because the mean of its divisors is an integer number (102644646).

Almost surely, 2^205289291 is an apocalyptic number.

205289291 is a deficient number, since it is larger than the sum of its proper divisors (1).

205289291 is an equidigital number, since it uses as much as digits as its factorization.

205289291 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 205289291 is about 14327.9199816303. The cubic root of 205289291 is about 589.9140840135.

The spelling of 205289291 in words is "two hundred five million, two hundred eighty-nine thousand, two hundred ninety-one".