9840640 has 72 divisors (see below), whose sum is σ = 24398010. Its totient is φ = 3809280.

The previous prime is 9840617. The next prime is 9840643. The reversal of 9840640 is 460489.

It can be written as a sum of positive squares in only one way, i.e., 8856576 + 984064 = 2976^2 + 992^2 .

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (9840643) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 317425 + ... + 317455.

Almost surely, 2^9840640 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 9840640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12199005).

9840640 is an abundant number, since it is smaller than the sum of its proper divisors (14557370).

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

9840640 is an equidigital number, since it uses as much as digits as its factorization.

9840640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89 (or 38 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 9840640 is about 3136.9794388870. The cubic root of 9840640 is about 214.2928996532.

The spelling of 9840640 in words is "nine million, eight hundred forty thousand, six hundred forty".