640532530 has 64 divisors (see below), whose sum is σ = 1298374272. Its totient is φ = 225469440.

The previous prime is 640532527. The next prime is 640532531. The reversal of 640532530 is 35235046.

It is not an unprimeable number, because it can be changed into a prime (640532531) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1371357 + ... + 1371823.

It is an arithmetic number, because the mean of its divisors is an integer number (20287098).

Almost surely, 2^640532530 is an apocalyptic number.

640532530 is an abundant number, since it is smaller than the sum of its proper divisors (657841742).

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

640532530 is a wasteful number, since it uses less digits than its factorization.

640532530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 859.

The product of its (nonzero) digits is 10800, while the sum is 28.

The square root of 640532530 is about 25308.7441411066. The cubic root of 640532530 is about 862.0128308123.

Adding to 640532530 its reverse (35235046), we get a palindrome (675767576).

The spelling of 640532530 in words is "six hundred forty million, five hundred thirty-two thousand, five hundred thirty".