7228728 has 48 divisors (see below), whose sum is σ = 21086520. Its totient is φ = 2223936.

The previous prime is 7228717. The next prime is 7228729. The reversal of 7228728 is 8278227.

7228728 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

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

It is a d-powerful number, because it can be written as 7⁵ + 2¹⁴ + 2¹⁹ + 8⁶ + 7⁶ + 2²² + 8⁷ .

It is a junction number, because it is equal to n+sod(n) for n = 7228692 and 7228701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7228729) 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, 2926 + ... + 4797.

Almost surely, 2^7228728 is an apocalyptic number.

7228728 is a gapful number since it is divisible by the number (78) formed by its first and last digit.

It is an amenable number.

7228728 is an abundant number, since it is smaller than the sum of its proper divisors (13857792).

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

7228728 is a wasteful number, since it uses less digits than its factorization.

7228728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7748 (or 7741 counting only the distinct ones).

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

The square root of 7228728 is about 2688.6293906003. The cubic root of 7228728 is about 193.3543562817.

The spelling of 7228728 in words is "seven million, two hundred twenty-eight thousand, seven hundred twenty-eight".