7840728 has 96 divisors (see below), whose sum is σ = 24860160. Its totient is φ = 2185920.

The previous prime is 7840727. The next prime is 7840733. The reversal of 7840728 is 8270487.

It is a super-2 number, since 2×7840728² = 122954031139968, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 7840692 and 7840701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7840727) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23523 + ... + 23853.

It is an arithmetic number, because the mean of its divisors is an integer number (258960).

Almost surely, 2^7840728 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 7840728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12430080).

7840728 is an abundant number, since it is smaller than the sum of its proper divisors (17019432).

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

7840728 is a wasteful number, since it uses less digits than its factorization.

7840728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397 (or 390 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 36.

The square root of 7840728 is about 2800.1299969823. The cubic root of 7840728 is about 198.6638264137.

The spelling of 7840728 in words is "seven million, eight hundred forty thousand, seven hundred twenty-eight".