644434434446 has 16 divisors (see below), whose sum is σ = 1054568083968. Its totient is φ = 292913907000.

The previous prime is 644434434433. The next prime is 644434434473.

644434434446 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 644434434394 and 644434434403.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82421 + ... + 1138271.

It is an arithmetic number, because the mean of its divisors is an integer number (65910505248).

Almost surely, 2^644434434446 is an apocalyptic number.

644434434446 is a deficient number, since it is larger than the sum of its proper divisors (410133649522).

644434434446 is a wasteful number, since it uses less digits than its factorization.

644434434446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1083607.

The product of its digits is 21233664, while the sum is 50.

The spelling of 644434434446 in words is "six hundred forty-four billion, four hundred thirty-four million, four hundred thirty-four thousand, four hundred forty-six".