644477312013 has 16 divisors (see below), whose sum is σ = 904547896320. Its totient is φ = 407030051376.

The previous prime is 644477311993. The next prime is 644477312021. The reversal of 644477312013 is 310213774446.

644477312013 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 644477312013 - 2¹² = 644477307917 is a prime.

It is a super-3 number, since 3×644477312013³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644477312033) 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, 4017756 + ... + 4175082.

It is an arithmetic number, because the mean of its divisors is an integer number (56534243520).

Almost surely, 2^644477312013 is an apocalyptic number.

It is an amenable number.

644477312013 is a deficient number, since it is larger than the sum of its proper divisors (260070584307).

644477312013 is a wasteful number, since it uses less digits than its factorization.

644477312013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229216.

The product of its (nonzero) digits is 338688, while the sum is 42.

The spelling of 644477312013 in words is "six hundred forty-four billion, four hundred seventy-seven million, three hundred twelve thousand, thirteen".