205650691 has 2 divisors, whose sum is σ = 205650692. Its totient is φ = 205650690.

The previous prime is 205650619. The next prime is 205650713. The reversal of 205650691 is 196056502.

It is a happy number.

Together with previous prime (205650619) 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-205650691 is a prime.

It is equal to p_11374396 and since 205650691 and 11374396 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (205650391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102825345 + 102825346.

It is an arithmetic number, because the mean of its divisors is an integer number (102825346).

Almost surely, 2^205650691 is an apocalyptic number.

205650691 is a deficient number, since it is larger than the sum of its proper divisors (1).

205650691 is an equidigital number, since it uses as much as digits as its factorization.

205650691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 34.

The square root of 205650691 is about 14340.5261758417. The cubic root of 205650691 is about 590.2600510231.

The spelling of 205650691 in words is "two hundred five million, six hundred fifty thousand, six hundred ninety-one".