9611721 has 12 divisors (see below), whose sum is σ = 15867072. Its totient is φ = 5492376.

The previous prime is 9611717. The next prime is 9611737. The reversal of 9611721 is 1271169.

It is not a de Polignac number, because 9611721 - 2² = 9611717 is a prime.

It is a Curzon number.

9611721 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (9611761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 76221 + ... + 76346.

It is an arithmetic number, because the mean of its divisors is an integer number (1322256).

Almost surely, 2^9611721 is an apocalyptic number.

It is an amenable number.

9611721 is a deficient number, since it is larger than the sum of its proper divisors (6255351).

9611721 is a wasteful number, since it uses less digits than its factorization.

9611721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152580 (or 152577 counting only the distinct ones).

The product of its digits is 756, while the sum is 27.

The square root of 9611721 is about 3100.2775682187. The cubic root of 9611721 is about 212.6181746381.

The spelling of 9611721 in words is "nine million, six hundred eleven thousand, seven hundred twenty-one".