68213815816 has 16 divisors (see below), whose sum is σ = 129074309100. Its totient is φ = 33794000064.

The previous prime is 68213815777. The next prime is 68213815843. The reversal of 68213815816 is 61851831286.

68213815816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 59022758916 + 9191056900 = 242946^2 + 95870^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 68213815816.

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, 39112555 + ... + 39114298.

Almost surely, 2^68213815816 is an apocalyptic number.

It is an amenable number.

68213815816 is a deficient number, since it is larger than the sum of its proper divisors (60860493284).

68213815816 is a wasteful number, since it uses less digits than its factorization.

68213815816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78226968 (or 78226964 counting only the distinct ones).

The product of its digits is 552960, while the sum is 49.

The spelling of 68213815816 in words is "sixty-eight billion, two hundred thirteen million, eight hundred fifteen thousand, eight hundred sixteen".