640687713848 has 384 divisors, whose sum is σ = 1623664627200. Its totient is φ = 230140984320.

The previous prime is 640687713847. The next prime is 640687713863. The reversal of 640687713848 is 848317786046.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (62).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640687713847) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2086930511 + ... + 2086930817.

It is an arithmetic number, because the mean of its divisors is an integer number (4228293300).

Almost surely, 2^640687713848 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 640687713848, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (811832313600).

640687713848 is an abundant number, since it is smaller than the sum of its proper divisors (982976913352).

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

640687713848 is a wasteful number, since it uses less digits than its factorization.

640687713848 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 571 (or 536 counting only the distinct ones).

The product of its (nonzero) digits is 43352064, while the sum is 62.

The spelling of 640687713848 in words is "six hundred forty billion, six hundred eighty-seven million, seven hundred thirteen thousand, eight hundred forty-eight".