205245717055 has 4 divisors (see below), whose sum is σ = 246294860472. Its totient is φ = 164196573640.

The previous prime is 205245717049. The next prime is 205245717163. The reversal of 205245717055 is 550717542502.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 205245717055 - 2⁷ = 205245716927 is a prime.

It is a super-2 number, since 2×205245717055² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20524571701 + ... + 20524571710.

It is an arithmetic number, because the mean of its divisors is an integer number (61573715118).

Almost surely, 2^205245717055 is an apocalyptic number.

205245717055 is a deficient number, since it is larger than the sum of its proper divisors (41049143417).

205245717055 is an equidigital number, since it uses as much as digits as its factorization.

205245717055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41049143416.

The product of its (nonzero) digits is 490000, while the sum is 43.

The spelling of 205245717055 in words is "two hundred five billion, two hundred forty-five million, seven hundred seventeen thousand, fifty-five".