9222721 has 8 divisors (see below), whose sum is σ = 9853704. Its totient is φ = 8601600.

The previous prime is 9222713. The next prime is 9222727. The reversal of 9222721 is 1272229.

9222721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 579121 + 8643600 = 761^2 + 2940^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9222721 - 2³ = 9222713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9222727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 480 + ... + 4321.

It is an arithmetic number, because the mean of its divisors is an integer number (1231713).

Almost surely, 2^9222721 is an apocalyptic number.

9222721 is the 1921-st heptagonal number.

It is an amenable number.

9222721 is a deficient number, since it is larger than the sum of its proper divisors (630983).

9222721 is a wasteful number, since it uses less digits than its factorization.

9222721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4931.

The product of its digits is 1008, while the sum is 25.

The square root of 9222721 is about 3036.8933138983. The cubic root of 9222721 is about 209.7102655958.

The spelling of 9222721 in words is "nine million, two hundred twenty-two thousand, seven hundred twenty-one".