640116520 has 32 divisors (see below), whose sum is σ = 1486725120. Its totient is φ = 247786560.

The previous prime is 640116509. The next prime is 640116553. The reversal of 640116520 is 25611046.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 256872 + ... + 259351.

It is an arithmetic number, because the mean of its divisors is an integer number (46460160).

Almost surely, 2^640116520 is an apocalyptic number.

It is an amenable number.

640116520 is an abundant number, since it is smaller than the sum of its proper divisors (846608600).

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

640116520 is a wasteful number, since it uses less digits than its factorization.

640116520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 516265 (or 516261 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 640116520 is about 25300.5241052434. The cubic root of 640116520 is about 861.8261717413.

Adding to 640116520 its reverse (25611046), we get a palindrome (665727566).

The spelling of 640116520 in words is "six hundred forty million, one hundred sixteen thousand, five hundred twenty".