8640918 has 80 divisors (see below), whose sum is σ = 22808016. Its totient is φ = 2410560.

The previous prime is 8640911. The next prime is 8640949. The reversal of 8640918 is 8190468.

It is a happy number.

8640918 is a `hidden beast` number, since 8 + 640 + 9 + 1 + 8 = 666.

8640918 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8640911) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 22980 + ... + 23352.

Almost surely, 2^8640918 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8640918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11404008).

8640918 is an abundant number, since it is smaller than the sum of its proper divisors (14167098).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8640918 is a wasteful number, since it uses less digits than its factorization.

8640918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 8640918 is about 2939.5438421633. The cubic root of 8640918 is about 205.2043807416.

The spelling of 8640918 in words is "eight million, six hundred forty thousand, nine hundred eighteen".