7640 has 16 divisors (see below), whose sum is σ = 17280.
Its totient is φ = 3040.
The previous prime is 7639. The next prime is 7643. The reversal of 7640 is 467.
It is a nialpdrome in base 10.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (7643) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56 + ... + 135.
It is an arithmetic number, because the mean of its divisors is an integer number (1080).
27640 is an apocalyptic number.
It is an amenable number.
7640 is an abundant number, since it is smaller than the sum of its proper divisors (9640).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8640).
7640 is a wasteful number, since it uses less digits than its factorization.
7640 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 202 (or 198 counting only the distinct ones).
The product of its (nonzero) digits is 168, while the sum is 17.
The square root of 7640 is about 87.4070935336.
The cubic root of 7640 is about 19.6953840096.
The spelling of 7640 in words is "seven thousand, six hundred forty".