640762322560 has 64 divisors (see below), whose sum is σ = 1533607005600. Its totient is φ = 256006333440.

The previous prime is 640762322539. The next prime is 640762322567. The reversal of 640762322560 is 65223267046.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (640762322567) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33006 + ... + 1132525.

Almost surely, 2^640762322560 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640762322560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (766803502800).

640762322560 is an abundant number, since it is smaller than the sum of its proper divisors (892844683040).

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

640762322560 is a wasteful number, since it uses less digits than its factorization.

640762322560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1166409 (or 1166397 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 43.

The spelling of 640762322560 in words is "six hundred forty billion, seven hundred sixty-two million, three hundred twenty-two thousand, five hundred sixty".