644486684446 has 64 divisors (see below), whose sum is σ = 1156118261760. Its totient is φ = 265987008000.

The previous prime is 644486684423. The next prime is 644486684489.

It is a happy number.

644486684446 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13327291 + ... + 13375561.

It is an arithmetic number, because the mean of its divisors is an integer number (18064347840).

Almost surely, 2^644486684446 is an apocalyptic number.

644486684446 is a deficient number, since it is larger than the sum of its proper divisors (511631577314).

644486684446 is a wasteful number, since it uses less digits than its factorization.

644486684446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49561.

The product of its digits is 339738624, while the sum is 64.

The spelling of 644486684446 in words is "six hundred forty-four billion, four hundred eighty-six million, six hundred eighty-four thousand, four hundred forty-six".