78065664 has 52 divisors (see below), whose sum is σ = 208182456. Its totient is φ = 26017792.

The previous prime is 78065639. The next prime is 78065677. The reversal of 78065664 is 46656087.

It is a happy number.

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, 9112 + ... + 15464.

Almost surely, 2^78065664 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 78065664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104091228).

78065664 is an abundant number, since it is smaller than the sum of its proper divisors (130116792).

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

78065664 is an equidigital number, since it uses as much as digits as its factorization.

78065664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6380 (or 6358 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 42.

The square root of 78065664 is about 8835.4775762264. The cubic root of 78065664 is about 427.3857319164.

The spelling of 78065664 in words is "seventy-eight million, sixty-five thousand, six hundred sixty-four".