644907471313 has 16 divisors (see below), whose sum is σ = 750230928000. Its totient is φ = 542900011392.

The previous prime is 644907471311. The next prime is 644907471337. The reversal of 644907471313 is 313174709446.

644907471313 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 644907471313 - 2¹ = 644907471311 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (644907471311) 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, 288868 + ... + 1171861.

It is an arithmetic number, because the mean of its divisors is an integer number (46889433000).

Almost surely, 2^644907471313 is an apocalyptic number.

It is an amenable number.

644907471313 is a deficient number, since it is larger than the sum of its proper divisors (105323456687).

644907471313 is a wasteful number, since it uses less digits than its factorization.

644907471313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1461864.

The product of its (nonzero) digits is 1524096, while the sum is 49.

The spelling of 644907471313 in words is "six hundred forty-four billion, nine hundred seven million, four hundred seventy-one thousand, three hundred thirteen".