644320117 has 8 divisors (see below), whose sum is σ = 736562816. Its totient is φ = 552126672.

The previous prime is 644320097. The next prime is 644320123. The reversal of 644320117 is 711023446.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 644320117 - 2¹¹ = 644318069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644320147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22168 + ... + 42190.

It is an arithmetic number, because the mean of its divisors is an integer number (92070352).

Almost surely, 2^644320117 is an apocalyptic number.

It is an amenable number.

644320117 is a deficient number, since it is larger than the sum of its proper divisors (92242699).

644320117 is a wasteful number, since it uses less digits than its factorization.

644320117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24627.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 644320117 is about 25383.4614857785. The cubic root of 644320117 is about 863.7085730699.

The spelling of 644320117 in words is "six hundred forty-four million, three hundred twenty thousand, one hundred seventeen".