721944576 has 200 divisors, whose sum is σ = 2283796350. Its totient is φ = 226492416.

The previous prime is 721944571. The next prime is 721944599. The reversal of 721944576 is 675449127.

721944576 is a `hidden beast` number, since 7 + 2 + 194 + 457 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 530841600 + 191102976 = 23040^2 + 13824^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721944571) 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 9 ways as a sum of consecutive naturals, for example, 42467320 + ... + 42467336.

Almost surely, 2^721944576 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 721944576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1141898175).

721944576 is an abundant number, since it is smaller than the sum of its proper divisors (1561851774).

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

721944576 is an frugal number, since it uses more digits than its factorization.

721944576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67 (or 22 counting only the distinct ones).

The product of its digits is 423360, while the sum is 45.

The square root of 721944576 is about 26869.0263314471. The cubic root of 721944576 is about 897.0871158442.

The spelling of 721944576 in words is "seven hundred twenty-one million, nine hundred forty-four thousand, five hundred seventy-six".