644377546 has 8 divisors (see below), whose sum is σ = 969336900. Its totient is φ = 321265248.

The previous prime is 644377529. The next prime is 644377549. The reversal of 644377546 is 645773446.

644377546 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 2 ways, for example, as 577873521 + 66504025 = 24039^2 + 8155^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 644377496 and 644377505.

It is not an unprimeable number, because it can be changed into a prime (644377549) 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, 460891 + ... + 462286.

Almost surely, 2^644377546 is an apocalyptic number.

644377546 is a deficient number, since it is larger than the sum of its proper divisors (324959354).

644377546 is a wasteful number, since it uses less digits than its factorization.

644377546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 923528.

The product of its digits is 1693440, while the sum is 46.

The square root of 644377546 is about 25384.5926892672. The cubic root of 644377546 is about 863.7342334234.

The spelling of 644377546 in words is "six hundred forty-four million, three hundred seventy-seven thousand, five hundred forty-six".