640932 has 12 divisors (see below), whose sum is σ = 1495536. Its totient is φ = 213640.

The previous prime is 640919. The next prime is 640933. The reversal of 640932 is 239046.

640932 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (640933) 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, 26694 + ... + 26717.

It is an arithmetic number, because the mean of its divisors is an integer number (124628).

2⁶⁴⁰⁹³² is an apocalyptic number.

It is an amenable number.

640932 is an abundant number, since it is smaller than the sum of its proper divisors (854604).

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

640932 is a wasteful number, since it uses less digits than its factorization.

640932 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53418 (or 53416 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 640932 is about 800.5822880879. The cubic root of 640932 is about 86.2191992520.

Adding to 640932 its reverse (239046), we get a palindrome (879978).

It can be divided in two parts, 6409 and 32, that added together give a triangular number (6441 = T₁₁₃).

The spelling of 640932 in words is "six hundred forty thousand, nine hundred thirty-two".