640871735916723 has 16 divisors (see below), whose sum is σ = 877590896503200. Its totient is φ = 415700219943936.

The previous prime is 640871735916619. The next prime is 640871735916767. The reversal of 640871735916723 is 327619537178046.

640871735916723 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 640871735916723 - 2¹² = 640871735912627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (640871735918723) 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, 189259203 + ... + 192615651.

It is an arithmetic number, because the mean of its divisors is an integer number (54849431031450).

It is a 1-persistent number, because it is pandigital, but 2⋅640871735916723 = 1281743471833446 is not.

Almost surely, 2^{640871735916723} is an apocalyptic number.

640871735916723 is a deficient number, since it is larger than the sum of its proper divisors (236719160586477).

640871735916723 is a wasteful number, since it uses less digits than its factorization.

640871735916723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5076646.

The product of its (nonzero) digits is 320060160, while the sum is 69.

The spelling of 640871735916723 in words is "six hundred forty trillion, eight hundred seventy-one billion, seven hundred thirty-five million, nine hundred sixteen thousand, seven hundred twenty-three".