205688035957 has 4 divisors (see below), whose sum is σ = 216513722080. Its totient is φ = 194862349836.

The previous prime is 205688035921. The next prime is 205688036011. The reversal of 205688035957 is 759530886502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 759530886502 = 2 ⋅379765443251.

It is a cyclic number.

It is not a de Polignac number, because 205688035957 - 2⁷ = 205688035829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205688035057) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5412843033 + ... + 5412843070.

It is an arithmetic number, because the mean of its divisors is an integer number (54128430520).

Almost surely, 2^205688035957 is an apocalyptic number.

It is an amenable number.

205688035957 is a deficient number, since it is larger than the sum of its proper divisors (10825686123).

205688035957 is a wasteful number, since it uses less digits than its factorization.

205688035957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10825686122.

The product of its (nonzero) digits is 18144000, while the sum is 58.

The spelling of 205688035957 in words is "two hundred five billion, six hundred eighty-eight million, thirty-five thousand, nine hundred fifty-seven".