205034306978 has 18 divisors (see below), whose sum is σ = 321527742417. Its totient is φ = 98052841920.

The previous prime is 205034306969. The next prime is 205034307017. The reversal of 205034306978 is 879603430502.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 203241377329 + 1792929649 = 450823^2 + 42343^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=320183.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 14721458 + ... + 14735378.

Almost surely, 2^205034306978 is an apocalyptic number.

205034306978 is a deficient number, since it is larger than the sum of its proper divisors (116493435439).

205034306978 is an frugal number, since it uses more digits than its factorization.

205034306978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27890 (or 13946 counting only the distinct ones).

The product of its (nonzero) digits is 1088640, while the sum is 47.

The spelling of 205034306978 in words is "two hundred five billion, thirty-four million, three hundred six thousand, nine hundred seventy-eight".