640520523260 has 12 divisors (see below), whose sum is σ = 1345093098888. Its totient is φ = 256208209296.

The previous prime is 640520523221. The next prime is 640520523277. The reversal of 640520523260 is 62325025046.

It is a self number, because there is not a number n which added to its sum of digits gives 640520523260.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16013013062 + ... + 16013013101.

It is an arithmetic number, because the mean of its divisors is an integer number (112091091574).

Almost surely, 2^640520523260 is an apocalyptic number.

It is an amenable number.

640520523260 is an abundant number, since it is smaller than the sum of its proper divisors (704572575628).

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

640520523260 is a wasteful number, since it uses less digits than its factorization.

640520523260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32026026172 (or 32026026170 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 35.

The spelling of 640520523260 in words is "six hundred forty billion, five hundred twenty million, five hundred twenty-three thousand, two hundred sixty".