78723840 has 288 divisors, whose sum is σ = 288449280. Its totient is φ = 18137088.

The previous prime is 78723839. The next prime is 78723941. The reversal of 78723840 is 4832787.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 948439 + ... + 948521.

It is an arithmetic number, because the mean of its divisors is an integer number (1001560).

Almost surely, 2^78723840 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 78723840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144224640).

78723840 is an abundant number, since it is smaller than the sum of its proper divisors (209725440).

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

78723840 is a wasteful number, since it uses less digits than its factorization.

78723840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 125 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 39.

The square root of 78723840 is about 8872.6456032009. The cubic root of 78723840 is about 428.5834764867.

The spelling of 78723840 in words is "seventy-eight million, seven hundred twenty-three thousand, eight hundred forty".