640512264 has 128 divisors (see below), whose sum is σ = 1953020160. Its totient is φ = 170876928.

The previous prime is 640512239. The next prime is 640512269. The reversal of 640512264 is 462215046.

It is not an unprimeable number, because it can be changed into a prime (640512269) 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, 390454 + ... + 392090.

It is an arithmetic number, because the mean of its divisors is an integer number (15257970).

Almost surely, 2^640512264 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 640512264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (976510080).

640512264 is an abundant number, since it is smaller than the sum of its proper divisors (1312507896).

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

640512264 is a wasteful number, since it uses less digits than its factorization.

640512264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1807 (or 1803 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 640512264 is about 25308.3437624828. The cubic root of 640512264 is about 862.0037395560.

The spelling of 640512264 in words is "six hundred forty million, five hundred twelve thousand, two hundred sixty-four".