644221122446 has 8 divisors (see below), whose sum is σ = 1054180018584. Its totient is φ = 292827782920.

The previous prime is 644221122439. The next prime is 644221122491.

644221122446 is nontrivially palindromic in base 10.

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

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 3 ways as a sum of consecutive naturals, for example, 14641389125 + ... + 14641389168.

It is an arithmetic number, because the mean of its divisors is an integer number (131772502323).

Almost surely, 2^644221122446 is an apocalyptic number.

644221122446 is a deficient number, since it is larger than the sum of its proper divisors (409958896138).

644221122446 is a wasteful number, since it uses less digits than its factorization.

644221122446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29282778306.

The product of its digits is 147456, while the sum is 38.

It can be divided in two parts, 644221 and 122446, that added together give a palindrome (766667).

The spelling of 644221122446 in words is "six hundred forty-four billion, two hundred twenty-one million, one hundred twenty-two thousand, four hundred forty-six".