78817728 has 112 divisors (see below), whose sum is σ = 231306624. Its totient is φ = 23485440.

The previous prime is 78817723. The next prime is 78817741. The reversal of 78817728 is 82771887.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78817723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141226 + ... + 141782.

Almost surely, 2^78817728 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 78817728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115653312).

78817728 is an abundant number, since it is smaller than the sum of its proper divisors (152488896).

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

78817728 is a wasteful number, since it uses less digits than its factorization.

78817728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650 (or 640 counting only the distinct ones).

The product of its digits is 351232, while the sum is 48.

The square root of 78817728 is about 8877.9348950080. The cubic root of 78817728 is about 428.7537885523.

The spelling of 78817728 in words is "seventy-eight million, eight hundred seventeen thousand, seven hundred twenty-eight".