4721728 has 56 divisors (see below), whose sum is σ = 10789920. Its totient is φ = 2027520.

The previous prime is 4721723. The next prime is 4721729. The reversal of 4721728 is 8271274.

It is a self number, because there is not a number n which added to its sum of digits gives 4721728.

It is not an unprimeable number, because it can be changed into a prime (4721723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13200 + ... + 13552.

Almost surely, 2^4721728 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 4721728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5394960).

4721728 is an abundant number, since it is smaller than the sum of its proper divisors (6068192).

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

4721728 is a wasteful number, since it uses less digits than its factorization.

4721728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395 (or 385 counting only the distinct ones).

The product of its digits is 6272, while the sum is 31.

The square root of 4721728 is about 2172.9537500831. The cubic root of 4721728 is about 167.7645985031.

The spelling of 4721728 in words is "four million, seven hundred twenty-one thousand, seven hundred twenty-eight".