78085728 has 96 divisors (see below), whose sum is σ = 260305920. Its totient is φ = 22308480.

The previous prime is 78085727. The next prime is 78085739. The reversal of 78085728 is 82758087.

It is a happy number.

78085728 is a `hidden beast` number, since 78 + 0 + 8 + 572 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78085723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 408 + ... + 12503.

It is an arithmetic number, because the mean of its divisors is an integer number (2711520).

Almost surely, 2^78085728 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 78085728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130152960).

78085728 is an abundant number, since it is smaller than the sum of its proper divisors (182220192).

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

78085728 is a wasteful number, since it uses less digits than its factorization.

78085728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12937 (or 12923 counting only the distinct ones).

The product of its (nonzero) digits is 250880, while the sum is 45.

The square root of 78085728 is about 8836.6129257765. The cubic root of 78085728 is about 427.4223435429.

The spelling of 78085728 in words is "seventy-eight million, eighty-five thousand, seven hundred twenty-eight".