9960721 has 4 divisors (see below), whose sum is σ = 10059444. Its totient is φ = 9862000.

The previous prime is 9960719. The next prime is 9960761. The reversal of 9960721 is 1270699.

9960721 is digitally balanced in base 3, 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, and also an emirpimes, since its reverse is a distinct semiprime: 1270699 = 17 ⋅74747.

It can be written as a sum of positive squares in 2 ways, for example, as 9828225 + 132496 = 3135^2 + 364^2 .

It is a cyclic number.

It is not a de Polignac number, because 9960721 - 2¹ = 9960719 is a prime.

It is a Duffinian number.

9960721 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (9960761) 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, 49210 + ... + 49411.

It is an arithmetic number, because the mean of its divisors is an integer number (2514861).

Almost surely, 2^9960721 is an apocalyptic number.

It is an amenable number.

9960721 is a deficient number, since it is larger than the sum of its proper divisors (98723).

9960721 is a wasteful number, since it uses less digits than its factorization.

9960721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98722.

The product of its (nonzero) digits is 6804, while the sum is 34.

The square root of 9960721 is about 3156.0609943409. The cubic root of 9960721 is about 215.1610187337.

The spelling of 9960721 in words is "nine million, nine hundred sixty thousand, seven hundred twenty-one".