722663721 has 16 divisors (see below), whose sum is σ = 1152968320. Its totient is φ = 444715920.

The previous prime is 722663701. The next prime is 722663743. The reversal of 722663721 is 127366227.

It is a happy number.

722663721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 722663721 - 2²² = 718469417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (722663701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1029085 + ... + 1029786.

It is an arithmetic number, because the mean of its divisors is an integer number (72060520).

Almost surely, 2^722663721 is an apocalyptic number.

It is an amenable number.

722663721 is a deficient number, since it is larger than the sum of its proper divisors (430304599).

722663721 is a wasteful number, since it uses less digits than its factorization.

722663721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2058893 (or 2058887 counting only the distinct ones).

The product of its digits is 42336, while the sum is 36.

The square root of 722663721 is about 26882.4054169265. The cubic root of 722663721 is about 897.3848864499.

The spelling of 722663721 in words is "seven hundred twenty-two million, six hundred sixty-three thousand, seven hundred twenty-one".