721788928 has 112 divisors (see below), whose sum is σ = 1695443904. Its totient is φ = 300810240.

The previous prime is 721788919. The next prime is 721788961. The reversal of 721788928 is 829887127.

It is a tau number, because it is divible by the number of its divisors (112).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2350951 + ... + 2351257.

It is an arithmetic number, because the mean of its divisors is an integer number (15137892).

Almost surely, 2^721788928 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 721788928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (847721952).

721788928 is an abundant number, since it is smaller than the sum of its proper divisors (973654976).

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

721788928 is an equidigital number, since it uses as much as digits as its factorization.

721788928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381 (or 357 counting only the distinct ones).

The product of its digits is 903168, while the sum is 52.

The square root of 721788928 is about 26866.1297547674. The cubic root of 721788928 is about 897.0226418962.

The spelling of 721788928 in words is "seven hundred twenty-one million, seven hundred eighty-eight thousand, nine hundred twenty-eight".