644326337 has 8 divisors (see below), whose sum is σ = 667860096. Its totient is φ = 621202032.

The previous prime is 644326237. The next prime is 644326343. The reversal of 644326337 is 733623446.

644326337 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 644326337 - 2¹² = 644322241 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 644326337.

It is not an unprimeable number, because it can be changed into a prime (644326037) 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, 99158 + ... + 105455.

It is an arithmetic number, because the mean of its divisors is an integer number (83482512).

Almost surely, 2^644326337 is an apocalyptic number.

644326337 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

It is an amenable number.

644326337 is a deficient number, since it is larger than the sum of its proper divisors (23533759).

644326337 is a wasteful number, since it uses less digits than its factorization.

644326337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204727.

The product of its digits is 217728, while the sum is 38.

The square root of 644326337 is about 25383.5840062037. The cubic root of 644326337 is about 863.7113523561.

The spelling of 644326337 in words is "six hundred forty-four million, three hundred twenty-six thousand, three hundred thirty-seven".