644045540446 has 32 divisors (see below), whose sum is σ = 1205176165632. Its totient is φ = 250775300160.

The previous prime is 644045540407. The next prime is 644045540513.

644045540446 is nontrivially palindromic in base 10.

644045540446 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 644045540396 and 644045540405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1006776 + ... + 1517131.

It is an arithmetic number, because the mean of its divisors is an integer number (37661755176).

Almost surely, 2^644045540446 is an apocalyptic number.

644045540446 is a deficient number, since it is larger than the sum of its proper divisors (561130625186).

644045540446 is a wasteful number, since it uses less digits than its factorization.

644045540446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2525584.

The product of its (nonzero) digits is 3686400, while the sum is 46.

The spelling of 644045540446 in words is "six hundred forty-four billion, forty-five million, five hundred forty thousand, four hundred forty-six".