7878728 has 64 divisors (see below), whose sum is σ = 17781120. Its totient is φ = 3225600.

The previous prime is 7878721. The next prime is 7878763. The reversal of 7878728 is 8278787.

It is not an unprimeable number, because it can be changed into a prime (7878721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81176 + ... + 81272.

It is an arithmetic number, because the mean of its divisors is an integer number (277830).

Almost surely, 2^7878728 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 7878728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8890560).

7878728 is an abundant number, since it is smaller than the sum of its proper divisors (9902392).

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

7878728 is a wasteful number, since it uses less digits than its factorization.

7878728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198 (or 194 counting only the distinct ones).

The product of its digits is 351232, while the sum is 47.

The square root of 7878728 is about 2806.9071947608. The cubic root of 7878728 is about 198.9842499929.

The spelling of 7878728 in words is "seven million, eight hundred seventy-eight thousand, seven hundred twenty-eight".