644522343 has 8 divisors (see below), whose sum is σ = 909913968. Its totient is φ = 404406144.

The previous prime is 644522321. The next prime is 644522371. The reversal of 644522343 is 343225446.

644522343 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 not a de Polignac number, because 644522343 - 2²⁰ = 643473767 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644522143) 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, 6318796 + ... + 6318897.

It is an arithmetic number, because the mean of its divisors is an integer number (113739246).

Almost surely, 2^644522343 is an apocalyptic number.

644522343 is a deficient number, since it is larger than the sum of its proper divisors (265391625).

644522343 is a wasteful number, since it uses less digits than its factorization.

644522343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12637713.

The product of its digits is 69120, while the sum is 33.

The square root of 644522343 is about 25387.4445937357. Note that the first 3 decimals coincide. The cubic root of 644522343 is about 863.7989246695.

Adding to 644522343 its reverse (343225446), we get a palindrome (987747789).

It can be divided in two parts, 64452 and 2343, that added together give a triangular number (66795 = T₃₆₅).

The spelling of 644522343 in words is "six hundred forty-four million, five hundred twenty-two thousand, three hundred forty-three".