78628850064817 has 12 divisors (see below), whose sum is σ = 89951237049436. Its totient is φ = 68311037157120.

The previous prime is 78628850064781. The next prime is 78628850064833. The reversal of 78628850064817 is 71846005882687.

It can be written as a sum of positive squares in 6 ways, for example, as 8938927958416 + 69689922106401 = 2989804^2 + 8348049^2 .

It is a de Polignac number, because none of the positive numbers 2^k-78628850064817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78628850064617) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10464309534 + ... + 10464317047.

Almost surely, 2^{78628850064817} is an apocalyptic number.

It is an amenable number.

78628850064817 is a deficient number, since it is larger than the sum of its proper divisors (11322386984619).

78628850064817 is a wasteful number, since it uses less digits than its factorization.

78628850064817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20928626628 (or 20928626611 counting only the distinct ones).

The product of its (nonzero) digits is 289013760, while the sum is 70.

The spelling of 78628850064817 in words is "seventy-eight trillion, six hundred twenty-eight billion, eight hundred fifty million, sixty-four thousand, eight hundred seventeen".