640471522056 has 16 divisors (see below), whose sum is σ = 1601178805200. Its totient is φ = 213490507344.

The previous prime is 640471522043. The next prime is 640471522081. The reversal of 640471522056 is 650225174046.

It is a junction number, because it is equal to n+sod(n) for n = 640471521999 and 640471522017.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13343156686 + ... + 13343156733.

It is an arithmetic number, because the mean of its divisors is an integer number (100073675325).

Almost surely, 2^640471522056 is an apocalyptic number.

It is an amenable number.

640471522056 is an abundant number, since it is smaller than the sum of its proper divisors (960707283144).

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

640471522056 is a wasteful number, since it uses less digits than its factorization.

640471522056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26686313428 (or 26686313424 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 42.

The spelling of 640471522056 in words is "six hundred forty billion, four hundred seventy-one million, five hundred twenty-two thousand, fifty-six".