205415591 has 2 divisors, whose sum is σ = 205415592. Its totient is φ = 205415590.

The previous prime is 205415569. The next prime is 205415597. The reversal of 205415591 is 195514502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 205415591 - 2¹⁸ = 205153447 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205415597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102707795 + 102707796.

It is an arithmetic number, because the mean of its divisors is an integer number (102707796).

Almost surely, 2^205415591 is an apocalyptic number.

205415591 is a deficient number, since it is larger than the sum of its proper divisors (1).

205415591 is an equidigital number, since it uses as much as digits as its factorization.

205415591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9000, while the sum is 32.

The square root of 205415591 is about 14332.3267824872. The cubic root of 205415591 is about 590.0350367013.

The spelling of 205415591 in words is "two hundred five million, four hundred fifteen thousand, five hundred ninety-one".