640735950976 has 128 divisors (see below), whose sum is σ = 1423057455360. Its totient is φ = 284862382080.

The previous prime is 640735950971. The next prime is 640735951001. The reversal of 640735950976 is 679059537046.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (640735950971) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 182180770 + ... + 182184286.

It is an arithmetic number, because the mean of its divisors is an integer number (11117636370).

Almost surely, 2^640735950976 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 640735950976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (711528727680).

640735950976 is an abundant number, since it is smaller than the sum of its proper divisors (782321504384).

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

640735950976 is a wasteful number, since it uses less digits than its factorization.

640735950976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6342 (or 6330 counting only the distinct ones).

The product of its (nonzero) digits is 42865200, while the sum is 61.

The spelling of 640735950976 in words is "six hundred forty billion, seven hundred thirty-five million, nine hundred fifty thousand, nine hundred seventy-six".