205311390770 has 16 divisors (see below), whose sum is σ = 382303969560. Its totient is φ = 79292674944.

The previous prime is 205311390743. The next prime is 205311390773. The reversal of 205311390770 is 77093113502.

205311390770 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 453113²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 107660765689 + 97650625081 = 328117^2 + 312491^2 .

It is not an unprimeable number, because it can be changed into a prime (205311390773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 353984867 + ... + 353985446.

Almost surely, 2^205311390770 is an apocalyptic number.

205311390770 is a deficient number, since it is larger than the sum of its proper divisors (176992578790).

205311390770 is a wasteful number, since it uses less digits than its factorization.

205311390770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707970349.

The product of its (nonzero) digits is 39690, while the sum is 38.

The spelling of 205311390770 in words is "two hundred five billion, three hundred eleven million, three hundred ninety thousand, seven hundred seventy".