640783383872 has 28 divisors (see below), whose sum is σ = 1271738132160. Its totient is φ = 320345429376.

The previous prime is 640783383841. The next prime is 640783383881. The reversal of 640783383872 is 278383387046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 273998 + ... + 1164749.

Almost surely, 2^640783383872 is an apocalyptic number.

It is an amenable number.

640783383872 is a deficient number, since it is larger than the sum of its proper divisors (630954748288).

640783383872 is a wasteful number, since it uses less digits than its factorization.

640783383872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1445718 (or 1445708 counting only the distinct ones).

The product of its (nonzero) digits is 32514048, while the sum is 59.

The spelling of 640783383872 in words is "six hundred forty billion, seven hundred eighty-three million, three hundred eighty-three thousand, eight hundred seventy-two".