205123216354 has 16 divisors (see below), whose sum is σ = 351646891200. Its totient is φ = 87908176944.

The previous prime is 205123216343. The next prime is 205123216369. The reversal of 205123216354 is 453612321502.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 766177 + ... + 998635.

It is an arithmetic number, because the mean of its divisors is an integer number (21977930700).

Almost surely, 2^205123216354 is an apocalyptic number.

205123216354 is a deficient number, since it is larger than the sum of its proper divisors (146523674846).

205123216354 is a wasteful number, since it uses less digits than its factorization.

205123216354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295497.

The product of its (nonzero) digits is 43200, while the sum is 34.

Adding to 205123216354 its reverse (453612321502), we get a palindrome (658735537856).

The spelling of 205123216354 in words is "two hundred five billion, one hundred twenty-three million, two hundred sixteen thousand, three hundred fifty-four".