640322360656 has 30 divisors (see below), whose sum is σ = 1363661725706. Its totient is φ = 291055617600.

The previous prime is 640322360567. The next prime is 640322360693. The reversal of 640322360656 is 656063223046.

It can be written as a sum of positive squares in only one way, i.e., 379185008400 + 261137352256 = 615780^2 + 511016^2 .

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 165370575 + ... + 165374446.

Almost surely, 2^640322360656 is an apocalyptic number.

It is an amenable number.

640322360656 is an abundant number, since it is smaller than the sum of its proper divisors (723339365050).

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

640322360656 is a wasteful number, since it uses less digits than its factorization.

640322360656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330745051 (or 330745034 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 43.

The spelling of 640322360656 in words is "six hundred forty billion, three hundred twenty-two million, three hundred sixty thousand, six hundred fifty-six".