640502016828 has 24 divisors (see below), whose sum is σ = 1508215761360. Its totient is φ = 211541950080.

The previous prime is 640502016793. The next prime is 640502016839. The reversal of 640502016828 is 828610205046.

It is a self number, because there is not a number n which added to its sum of digits gives 640502016828.

It is a congruent number.

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, 244838913 + ... + 244841528.

It is an arithmetic number, because the mean of its divisors is an integer number (62842323390).

Almost surely, 2^640502016828 is an apocalyptic number.

It is an amenable number.

640502016828 is an abundant number, since it is smaller than the sum of its proper divisors (867713744532).

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

640502016828 is a wasteful number, since it uses less digits than its factorization.

640502016828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489680557 (or 489680555 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 42.

The spelling of 640502016828 in words is "six hundred forty billion, five hundred two million, sixteen thousand, eight hundred twenty-eight".