640248740637 has 16 divisors (see below), whose sum is σ = 931286330688. Its totient is φ = 388023108480.

The previous prime is 640248740633. The next prime is 640248740647. The reversal of 640248740637 is 736047842046.

640248740637 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 640248740637 - 2² = 640248740633 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 640248740637.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640248740633) 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, 2535063 + ... + 2776155.

It is an arithmetic number, because the mean of its divisors is an integer number (58205395668).

Almost surely, 2^640248740637 is an apocalyptic number.

It is an amenable number.

640248740637 is a deficient number, since it is larger than the sum of its proper divisors (291037590051).

640248740637 is a wasteful number, since it uses less digits than its factorization.

640248740637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321580.

The product of its (nonzero) digits is 5419008, while the sum is 51.

The spelling of 640248740637 in words is "six hundred forty billion, two hundred forty-eight million, seven hundred forty thousand, six hundred thirty-seven".