644652323 has 4 divisors (see below), whose sum is σ = 736745520. Its totient is φ = 552559128.

The previous prime is 644652319. The next prime is 644652343. The reversal of 644652323 is 323256446.

644652323 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 a cyclic number.

It is not a de Polignac number, because 644652323 - 2² = 644652319 is a prime.

It is not an unprimeable number, because it can be changed into a prime (644652343) 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, 46046588 + ... + 46046601.

It is an arithmetic number, because the mean of its divisors is an integer number (184186380).

Almost surely, 2^644652323 is an apocalyptic number.

644652323 is a deficient number, since it is larger than the sum of its proper divisors (92093197).

644652323 is an equidigital number, since it uses as much as digits as its factorization.

644652323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92093196.

The product of its digits is 103680, while the sum is 35.

The square root of 644652323 is about 25390.0043914923. The cubic root of 644652323 is about 863.8569878428.

The spelling of 644652323 in words is "six hundred forty-four million, six hundred fifty-two thousand, three hundred twenty-three".