8321640 has 64 divisors (see below), whose sum is σ = 25781760. Its totient is φ = 2146560.

The previous prime is 8321627. The next prime is 8321657. The reversal of 8321640 is 461238.

It is a happy number.

8321640 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 8321640.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2602 + ... + 4838.

It is an arithmetic number, because the mean of its divisors is an integer number (402840).

Almost surely, 2^8321640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8321640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12890880).

8321640 is an abundant number, since it is smaller than the sum of its proper divisors (17460120).

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

8321640 is a wasteful number, since it uses less digits than its factorization.

8321640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2282 (or 2278 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 8321640 is about 2884.7252902140. The cubic root of 8321640 is about 202.6451938430.

Adding to 8321640 its reverse (461238), we get a palindrome (8782878).

The spelling of 8321640 in words is "eight million, three hundred twenty-one thousand, six hundred forty".