78643650065 has 32 divisors (see below), whose sum is σ = 97164531072. Its totient is φ = 61084800000.

The previous prime is 78643650023. The next prime is 78643650073. The reversal of 78643650065 is 56005634687.

It is not a de Polignac number, because 78643650065 - 2¹⁰ = 78643649041 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78643649995 and 78643650022.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8646170 + ... + 8655260.

It is an arithmetic number, because the mean of its divisors is an integer number (3036391596).

Almost surely, 2^78643650065 is an apocalyptic number.

It is an amenable number.

78643650065 is a deficient number, since it is larger than the sum of its proper divisors (18520881007).

78643650065 is a wasteful number, since it uses less digits than its factorization.

78643650065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9521.

The product of its (nonzero) digits is 3628800, while the sum is 50.

The spelling of 78643650065 in words is "seventy-eight billion, six hundred forty-three million, six hundred fifty thousand, sixty-five".