78806612664 has 384 divisors, whose sum is σ = 257095238400. Its totient is φ = 22406077440.

The previous prime is 78806612657. The next prime is 78806612719. The reversal of 78806612664 is 46621660887.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 78806612664.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 19684887 + ... + 19688889.

It is an arithmetic number, because the mean of its divisors is an integer number (669518850).

Almost surely, 2^78806612664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78806612664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128547619200).

78806612664 is an abundant number, since it is smaller than the sum of its proper divisors (178288625736).

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

78806612664 is a wasteful number, since it uses less digits than its factorization.

78806612664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4097 (or 4081 counting only the distinct ones).

The product of its (nonzero) digits is 4644864, while the sum is 54.

The spelling of 78806612664 in words is "seventy-eight billion, eight hundred six million, six hundred twelve thousand, six hundred sixty-four".