7813728 has 72 divisors (see below), whose sum is σ = 23941008. Its totient is φ = 2403072.

The previous prime is 7813723. The next prime is 7813753. The reversal of 7813728 is 8273187.

7813728 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×7813728² = 122108690515968, 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 = 7813692 and 7813701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7813723) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2701 + ... + 4787.

It is an arithmetic number, because the mean of its divisors is an integer number (332514).

Almost surely, 2^7813728 is an apocalyptic number.

7813728 is a gapful number since it is divisible by the number (78) 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 7813728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11970504).

7813728 is an abundant number, since it is smaller than the sum of its proper divisors (16127280).

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

7813728 is a wasteful number, since it uses less digits than its factorization.

7813728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2116 (or 2105 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 7813728 is about 2795.3046345613. The cubic root of 7813728 is about 198.4355273700.

The spelling of 7813728 in words is "seven million, eight hundred thirteen thousand, seven hundred twenty-eight".