644375343 has 4 divisors (see below), whose sum is σ = 859167128. Its totient is φ = 429583560.

The previous prime is 644375317. The next prime is 644375351. The reversal of 644375343 is 343573446.

644375343 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 644375343 - 2⁶ = 644375279 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 (644375353) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107395888 + ... + 107395893.

It is an arithmetic number, because the mean of its divisors is an integer number (214791782).

Almost surely, 2^644375343 is an apocalyptic number.

644375343 is a deficient number, since it is larger than the sum of its proper divisors (214791785).

644375343 is a wasteful number, since it uses less digits than its factorization.

644375343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214791784.

The product of its digits is 362880, while the sum is 39.

The square root of 644375343 is about 25384.5492967671. The cubic root of 644375343 is about 863.7332491099.

The spelling of 644375343 in words is "six hundred forty-four million, three hundred seventy-five thousand, three hundred forty-three".