9256721 has 4 divisors (see below), whose sum is σ = 9801252. Its totient is φ = 8712192.

The previous prime is 9256703. The next prime is 9256729. The reversal of 9256721 is 1276529.

9256721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5013121 + 4243600 = 2239^2 + 2060^2 .

It is a cyclic number.

It is not a de Polignac number, because 9256721 - 2⁶ = 9256657 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9256729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 272240 + ... + 272273.

It is an arithmetic number, because the mean of its divisors is an integer number (2450313).

Almost surely, 2^9256721 is an apocalyptic number.

It is an amenable number.

9256721 is a deficient number, since it is larger than the sum of its proper divisors (544531).

9256721 is a wasteful number, since it uses less digits than its factorization.

9256721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 544530.

The product of its digits is 7560, while the sum is 32.

The square root of 9256721 is about 3042.4859901074. The cubic root of 9256721 is about 209.9676518579.

The spelling of 9256721 in words is "nine million, two hundred fifty-six thousand, seven hundred twenty-one".