8640909 has 12 divisors (see below), whose sum is σ = 12884352. Its totient is φ = 5574600.

The previous prime is 8640889. The next prime is 8640911. The reversal of 8640909 is 9090468.

8640909 is a `hidden beast` number, since 8 + 640 + 9 + 0 + 9 = 666.

8640909 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 8640909 - 2⁷ = 8640781 is a prime.

8640909 is a modest number, since divided by 909 gives 864 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8640949) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15207 + ... + 15764.

It is an arithmetic number, because the mean of its divisors is an integer number (1073696).

Almost surely, 2^8640909 is an apocalyptic number.

It is an amenable number.

8640909 is a deficient number, since it is larger than the sum of its proper divisors (4243443).

8640909 is a wasteful number, since it uses less digits than its factorization.

8640909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31008 (or 31005 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 8640909 is about 2939.5423113131. The cubic root of 8640909 is about 205.2043094976.

The spelling of 8640909 in words is "eight million, six hundred forty thousand, nine hundred nine".