9243721 has 4 divisors (see below), whose sum is σ = 9562500. Its totient is φ = 8924944.

The previous prime is 9243713. The next prime is 9243743. The reversal of 9243721 is 1273429.

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 2295225 + 6948496 = 1515^2 + 2636^2 .

It is a cyclic number.

It is not a de Polignac number, because 9243721 - 2³ = 9243713 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 9243721.

It is not an unprimeable number, because it can be changed into a prime (9243761) 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, 159346 + ... + 159403.

It is an arithmetic number, because the mean of its divisors is an integer number (2390625).

Almost surely, 2^9243721 is an apocalyptic number.

It is an amenable number.

9243721 is a deficient number, since it is larger than the sum of its proper divisors (318779).

9243721 is a wasteful number, since it uses less digits than its factorization.

9243721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318778.

The product of its digits is 3024, while the sum is 28.

The square root of 9243721 is about 3040.3488286708. The cubic root of 9243721 is about 209.8693140028.

The spelling of 9243721 in words is "nine million, two hundred forty-three thousand, seven hundred twenty-one".