664551561105256 has 32 divisors (see below), whose sum is σ = 1359695194761600. Its totient is φ = 301983295098240.

The previous prime is 664551561105239. The next prime is 664551561105259. The reversal of 664551561105256 is 652501165155466.

It is a self number, because there is not a number n which added to its sum of digits gives 664551561105256.

It is not an unprimeable number, because it can be changed into a prime (664551561105259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1069641600 + ... + 1070262703.

It is an arithmetic number, because the mean of its divisors is an integer number (42490474836300).

Almost surely, 2^{664551561105256} is an apocalyptic number.

It is an amenable number.

664551561105256 is an abundant number, since it is smaller than the sum of its proper divisors (695143633656344).

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

664551561105256 is a wasteful number, since it uses less digits than its factorization.

664551561105256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2139907849 (or 2139907845 counting only the distinct ones).

The product of its (nonzero) digits is 32400000, while the sum is 58.

The spelling of 664551561105256 in words is "six hundred sixty-four trillion, five hundred fifty-one billion, five hundred sixty-one million, one hundred five thousand, two hundred fifty-six".