644063443546345 has 8 divisors (see below), whose sum is σ = 772877419797960. Its totient is φ = 515249896475520.

The previous prime is 644063443546343. The next prime is 644063443546349. The reversal of 644063443546345 is 543645344360446.

644063443546345 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 60971297961744 + 583092145584601 = 7808412^2 + 24147301^2 .

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

It is not a de Polignac number, because 644063443546345 - 2¹ = 644063443546343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (644063443546343) 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, 103984410 + ... + 110004019.

It is an arithmetic number, because the mean of its divisors is an integer number (96609677474745).

Almost surely, 2^{644063443546345} is an apocalyptic number.

It is an amenable number.

644063443546345 is a deficient number, since it is larger than the sum of its proper divisors (128813976251615).

644063443546345 is a wasteful number, since it uses less digits than its factorization.

644063443546345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214590395.

The product of its (nonzero) digits is 597196800, while the sum is 61.

The spelling of 644063443546345 in words is "six hundred forty-four trillion, sixty-three billion, four hundred forty-three million, five hundred forty-six thousand, three hundred forty-five".