78987798 has 40 divisors (see below), whose sum is σ = 178218480. Its totient is φ = 26146800.

The previous prime is 78987787. The next prime is 78987803. The reversal of 78987798 is 89778987.

It is a congruent number.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 22848 + ... + 26076.

It is an arithmetic number, because the mean of its divisors is an integer number (4455462).

Almost surely, 2^78987798 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78987798, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89109240).

78987798 is an abundant number, since it is smaller than the sum of its proper divisors (99230682).

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

78987798 is a wasteful number, since it uses less digits than its factorization.

78987798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3394 (or 3385 counting only the distinct ones).

The product of its digits is 14224896, while the sum is 63.

The square root of 78987798 is about 8887.5079746800. The cubic root of 78987798 is about 429.0619500736.

The spelling of 78987798 in words is "seventy-eight million, nine hundred eighty-seven thousand, seven hundred ninety-eight".