644326444623446 has 32 divisors (see below), whose sum is σ = 1042102838181888. Its totient is φ = 297019244766240.

The previous prime is 644326444623427. The next prime is 644326444623487.

644326444623446 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 381658331 + ... + 383342841.

It is an arithmetic number, because the mean of its divisors is an integer number (32565713693184).

Almost surely, 2^{644326444623446} is an apocalyptic number.

644326444623446 is a deficient number, since it is larger than the sum of its proper divisors (397776393558442).

644326444623446 is a wasteful number, since it uses less digits than its factorization.

644326444623446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1702436.

The product of its digits is 764411904, while the sum is 62.

The spelling of 644326444623446 in words is "six hundred forty-four trillion, three hundred twenty-six billion, four hundred forty-four million, six hundred twenty-three thousand, four hundred forty-six".