8640857 has 8 divisors (see below), whose sum is σ = 8790600. Its totient is φ = 8492544.

The previous prime is 8640823. The next prime is 8640859. The reversal of 8640857 is 7580468.

8640857 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1901641 + 6739216 = 1379^2 + 2596^2 .

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

It is not a de Polignac number, because 8640857 - 2⁸ = 8640601 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8640857.

It is not an unprimeable number, because it can be changed into a prime (8640859) 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, 22019 + ... + 22407.

It is an arithmetic number, because the mean of its divisors is an integer number (1098825).

Almost surely, 2^8640857 is an apocalyptic number.

It is an amenable number.

8640857 is a deficient number, since it is larger than the sum of its proper divisors (149743).

8640857 is a wasteful number, since it uses less digits than its factorization.

8640857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 715.

The product of its (nonzero) digits is 53760, while the sum is 38.

The square root of 8640857 is about 2939.5334663854. The cubic root of 8640857 is about 205.2038978648.

The spelling of 8640857 in words is "eight million, six hundred forty thousand, eight hundred fifty-seven".