7685640 has 96 divisors (see below), whose sum is σ = 25697880. Its totient is φ = 1990656.

The previous prime is 7685627. The next prime is 7685641. The reversal of 7685640 is 465867.

It is a happy number.

7685640 is a `hidden beast` number, since 7 + 6 + 8 + 5 + 640 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 7584516 + 101124 = 2754^2 + 318^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 7685595 and 7685604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7685641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13032 + ... + 13608.

Almost surely, 2^7685640 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 7685640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12848940).

7685640 is an abundant number, since it is smaller than the sum of its proper divisors (18012240).

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

7685640 is a wasteful number, since it uses less digits than its factorization.

7685640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 631 (or 624 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 7685640 is about 2772.2986852069. The cubic root of 7685640 is about 197.3452507818.

The spelling of 7685640 in words is "seven million, six hundred eighty-five thousand, six hundred forty".