78828090 has 64 divisors (see below), whose sum is σ = 213528960. Its totient is φ = 18448640.

The previous prime is 78828089. The next prime is 78828091. The reversal of 78828090 is 9082887.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (78828089) and next prime (78828091).

It is not an unprimeable number, because it can be changed into a prime (78828091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5452 + ... + 13688.

It is an arithmetic number, because the mean of its divisors is an integer number (3336390).

Almost surely, 2^78828090 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78828090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106764480).

78828090 is an abundant number, since it is smaller than the sum of its proper divisors (134700870).

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

78828090 is a wasteful number, since it uses less digits than its factorization.

78828090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8287.

The product of its (nonzero) digits is 64512, while the sum is 42.

The square root of 78828090 is about 8878.5184574905. The cubic root of 78828090 is about 428.7725768469.

The spelling of 78828090 in words is "seventy-eight million, eight hundred twenty-eight thousand, ninety".