9940721 has 8 divisors (see below), whose sum is σ = 11380224. Its totient is φ = 8506080.

The previous prime is 9940717. The next prime is 9940729. The reversal of 9940721 is 1270499.

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 9940721 - 2² = 9940717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9940729) 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, 6221 + ... + 7653.

It is an arithmetic number, because the mean of its divisors is an integer number (1422528).

Almost surely, 2^9940721 is an apocalyptic number.

It is an amenable number.

9940721 is a deficient number, since it is larger than the sum of its proper divisors (1439503).

9940721 is a wasteful number, since it uses less digits than its factorization.

9940721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2431.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 9940721 is about 3152.8908956702. The cubic root of 9940721 is about 215.0169159216.

The spelling of 9940721 in words is "nine million, nine hundred forty thousand, seven hundred twenty-one".