644326849 has 8 divisors (see below), whose sum is σ = 663505920. Its totient is φ = 625312800.

The previous prime is 644326829. The next prime is 644326861. The reversal of 644326849 is 948623446.

644326849 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 644326849 - 2⁷ = 644326721 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 644326799 and 644326808.

It is not an unprimeable number, because it can be changed into a prime (644326819) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33309 + ... + 48970.

It is an arithmetic number, because the mean of its divisors is an integer number (82938240).

Almost surely, 2^644326849 is an apocalyptic number.

It is an amenable number.

644326849 is a deficient number, since it is larger than the sum of its proper divisors (19179071).

644326849 is a wasteful number, since it uses less digits than its factorization.

644326849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82511.

The product of its digits is 995328, while the sum is 46.

The square root of 644326849 is about 25383.5940914599. The cubic root of 644326849 is about 863.7115811325.

The spelling of 644326849 in words is "six hundred forty-four million, three hundred twenty-six thousand, eight hundred forty-nine".