644323463 has 4 divisors (see below), whose sum is σ = 736369680. Its totient is φ = 552277248.

The previous prime is 644323453. The next prime is 644323543. The reversal of 644323463 is 364323446.

644323463 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 644323463 - 2⁶ = 644323399 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 (644323453) 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, 46023098 + ... + 46023111.

It is an arithmetic number, because the mean of its divisors is an integer number (184092420).

Almost surely, 2^644323463 is an apocalyptic number.

644323463 is a deficient number, since it is larger than the sum of its proper divisors (92046217).

644323463 is an equidigital number, since it uses as much as digits as its factorization.

644323463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92046216.

The product of its digits is 124416, while the sum is 35.

The square root of 644323463 is about 25383.5273947495. The cubic root of 644323463 is about 863.7100681672.

The spelling of 644323463 in words is "six hundred forty-four million, three hundred twenty-three thousand, four hundred sixty-three".