640493045448 has 32 divisors (see below), whose sum is σ = 1601512064160. Its totient is φ = 213460421760.

The previous prime is 640493045417. The next prime is 640493045471. The reversal of 640493045448 is 844540394046.

It is a self number, because there is not a number n which added to its sum of digits gives 640493045448.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2188198 + ... + 2463573.

It is an arithmetic number, because the mean of its divisors is an integer number (50047252005).

Almost surely, 2^640493045448 is an apocalyptic number.

It is an amenable number.

640493045448 is an abundant number, since it is smaller than the sum of its proper divisors (961019018712).

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

640493045448 is a wasteful number, since it uses less digits than its factorization.

640493045448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4657517 (or 4657513 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 51.

The spelling of 640493045448 in words is "six hundred forty billion, four hundred ninety-three million, forty-five thousand, four hundred forty-eight".