78784640 has 192 divisors, whose sum is σ = 223845120. Its totient is φ = 26265600.

The previous prime is 78784627. The next prime is 78784691. The reversal of 78784640 is 4648787.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 78784591 and 78784600.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2541425 + ... + 2541455.

It is an arithmetic number, because the mean of its divisors is an integer number (1165860).

Almost surely, 2^78784640 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 78784640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111922560).

78784640 is an abundant number, since it is smaller than the sum of its proper divisors (145060480).

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

78784640 is a wasteful number, since it uses less digits than its factorization.

78784640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99 (or 68 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 44.

The square root of 78784640 is about 8876.0712029591. The cubic root of 78784640 is about 428.6937826316.

The spelling of 78784640 in words is "seventy-eight million, seven hundred eighty-four thousand, six hundred forty".