78919400 has 72 divisors (see below), whose sum is σ = 213471270. Its totient is φ = 27054720.

The previous prime is 78919387. The next prime is 78919429. The reversal of 78919400 is 491987.

It can be written as a sum of positive squares in 3 ways, for example, as 67535524 + 11383876 = 8218^2 + 3374^2 .

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 5774 + ... + 13826.

Almost surely, 2^78919400 is an apocalyptic number.

78919400 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78919400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106735635).

78919400 is an abundant number, since it is smaller than the sum of its proper divisors (134551870).

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

78919400 is a wasteful number, since it uses less digits than its factorization.

78919400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8083 (or 8067 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 78919400 is about 8883.6591560010. The cubic root of 78919400 is about 428.9380682636.

The spelling of 78919400 in words is "seventy-eight million, nine hundred nineteen thousand, four hundred".