6720728 has 32 divisors (see below), whose sum is σ = 14741760. Its totient is φ = 2812320.

The previous prime is 6720719. The next prime is 6720731. The reversal of 6720728 is 8270276.

It is a d-powerful number, because it can be written as 6⁴ + 7⁷ + 2³ + 0 + 7⁸ + 2¹⁷ + 8 .

It is a junction number, because it is equal to n+sod(n) for n = 6720694 and 6720703.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1013 + ... + 3803.

It is an arithmetic number, because the mean of its divisors is an integer number (460680).

Almost surely, 2^6720728 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 6720728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7370880).

6720728 is an abundant number, since it is smaller than the sum of its proper divisors (8021032).

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

6720728 is a wasteful number, since it uses less digits than its factorization.

6720728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2847 (or 2843 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 6720728 is about 2592.4366916089. The cubic root of 6720728 is about 188.7145734135.

The spelling of 6720728 in words is "six million, seven hundred twenty thousand, seven hundred twenty-eight".