9389721 has 12 divisors (see below), whose sum is σ = 13761776. Its totient is φ = 5690520.

The previous prime is 9389719. The next prime is 9389741. The reversal of 9389721 is 1279839.

9389721 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 9389721 - 2¹ = 9389719 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 9389721.

It is not an unprimeable number, because it can be changed into a prime (9389741) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12571 + ... + 13296.

Almost surely, 2^9389721 is an apocalyptic number.

It is an amenable number.

9389721 is a deficient number, since it is larger than the sum of its proper divisors (4372055).

9389721 is a wasteful number, since it uses less digits than its factorization.

9389721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25892 (or 25881 counting only the distinct ones).

The product of its digits is 27216, while the sum is 39.

The square root of 9389721 is about 3064.2651647663. The cubic root of 9389721 is about 210.9684745845.

The spelling of 9389721 in words is "nine million, three hundred eighty-nine thousand, seven hundred twenty-one".