7878818864 has 20 divisors (see below), whose sum is σ = 17445956304. Its totient is φ = 3376636608.

The previous prime is 7878818819. The next prime is 7878818867. The reversal of 7878818864 is 4688188787.

It is a self number, because there is not a number n which added to its sum of digits gives 7878818864.

It is not an unprimeable number, because it can be changed into a prime (7878818867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35173187 + ... + 35173410.

Almost surely, 2^7878818864 is an apocalyptic number.

It is an amenable number.

7878818864 is an abundant number, since it is smaller than the sum of its proper divisors (9567137440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7878818864 is a wasteful number, since it uses less digits than its factorization.

7878818864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70346612 (or 70346606 counting only the distinct ones).

The product of its digits is 38535168, while the sum is 65.

The square root of 7878818864 is about 88762.7109996084. The cubic root of 7878818864 is about 1989.8501494024.

The spelling of 7878818864 in words is "seven billion, eight hundred seventy-eight million, eight hundred eighteen thousand, eight hundred sixty-four".