9996721 has 8 divisors (see below), whose sum is σ = 11447744. Its totient is φ = 8551440.

The previous prime is 9996719. The next prime is 9996737. The reversal of 9996721 is 1276999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9996721 - 2¹ = 9996719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9996751) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3391 + ... + 5611.

It is an arithmetic number, because the mean of its divisors is an integer number (1430968).

Almost surely, 2^9996721 is an apocalyptic number.

It is an amenable number.

9996721 is a deficient number, since it is larger than the sum of its proper divisors (1451023).

9996721 is a wasteful number, since it uses less digits than its factorization.

9996721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2871.

The product of its digits is 61236, while the sum is 43.

The square root of 9996721 is about 3161.7591622386. The cubic root of 9996721 is about 215.4199184578.

The spelling of 9996721 in words is "nine million, nine hundred ninety-six thousand, seven hundred twenty-one".