8936721 has 24 divisors (see below), whose sum is σ = 13563264. Its totient is φ = 5663520.

The previous prime is 8936663. The next prime is 8936731. The reversal of 8936721 is 1276398.

8936721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 8936721 - 2⁶ = 8936657 is a prime.

8936721 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8936731) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15366 + ... + 15936.

It is an arithmetic number, because the mean of its divisors is an integer number (565136).

Almost surely, 2^8936721 is an apocalyptic number.

It is an amenable number.

8936721 is a deficient number, since it is larger than the sum of its proper divisors (4626543).

8936721 is a wasteful number, since it uses less digits than its factorization.

8936721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661 (or 658 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 8936721 is about 2989.4348964311. The cubic root of 8936721 is about 207.5197329663.

The spelling of 8936721 in words is "eight million, nine hundred thirty-six thousand, seven hundred twenty-one".