205820632057 has 4 divisors (see below), whose sum is σ = 205821657216. Its totient is φ = 205819606900.

The previous prime is 205820632027. The next prime is 205820632091. The reversal of 205820632057 is 750236028502.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205820632057 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205820632027) 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, 101569 + ... + 649582.

It is an arithmetic number, because the mean of its divisors is an integer number (51455414304).

Almost surely, 2^205820632057 is an apocalyptic number.

It is an amenable number.

205820632057 is a deficient number, since it is larger than the sum of its proper divisors (1025159).

205820632057 is an equidigital number, since it uses as much as digits as its factorization.

205820632057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1025158.

The product of its (nonzero) digits is 201600, while the sum is 40.

The spelling of 205820632057 in words is "two hundred five billion, eight hundred twenty million, six hundred thirty-two thousand, fifty-seven".