8640660 has 72 divisors (see below), whose sum is σ = 28153440. Its totient is φ = 1974336.

The previous prime is 8640601. The next prime is 8640679. The reversal of 8640660 is 660468.

It is a happy number.

It is a super-2 number, since 2×8640660² = 149322010471200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1471 + ... + 4409.

It is an arithmetic number, because the mean of its divisors is an integer number (391020).

Almost surely, 2^8640660 is an apocalyptic number.

It is a pronic number, being equal to 2939×2940.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8640660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14076720).

8640660 is an abundant number, since it is smaller than the sum of its proper divisors (19512780).

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

8640660 is a wasteful number, since it uses less digits than its factorization.

8640660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2965 (or 2956 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 8640660 is about 2939.4999574758. The cubic root of 8640660 is about 205.2023383947.

The spelling of 8640660 in words is "eight million, six hundred forty thousand, six hundred sixty".