78455664 has 90 divisors (see below), whose sum is σ = 255437520. Its totient is φ = 22413888.

The previous prime is 78455633. The next prime is 78455669. The reversal of 78455664 is 46655487.

78455664 is a `hidden beast` number, since 7 + 84 + 5 + 566 + 4 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78455669) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1497 + ... + 12615.

Almost surely, 2^78455664 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 78455664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127718760).

78455664 is an abundant number, since it is smaller than the sum of its proper divisors (176981856).

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

78455664 is a wasteful number, since it uses less digits than its factorization.

78455664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11147 (or 11131 counting only the distinct ones).

The product of its digits is 806400, while the sum is 45.

The square root of 78455664 is about 8857.5201947272. The cubic root of 78455664 is about 428.0962604112.

The spelling of 78455664 in words is "seventy-eight million, four hundred fifty-five thousand, six hundred sixty-four".