644422224446 has 32 divisors (see below), whose sum is σ = 1297857351168. Its totient is φ = 231760239840.

The previous prime is 644422224443. The next prime is 644422224451.

644422224446 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 644422224397 and 644422224406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644422224443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 160942610 + ... + 160946613.

It is an arithmetic number, because the mean of its divisors is an integer number (40558042224).

Almost surely, 2^644422224446 is an apocalyptic number.

644422224446 is an abundant number, since it is smaller than the sum of its proper divisors (653435126722).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644422224446 is a wasteful number, since it uses less digits than its factorization.

644422224446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321889256.

The product of its digits is 2359296, while the sum is 44.

It can be divided in two parts, 644422 and 224446, that added together give a palindrome (868868).

The spelling of 644422224446 in words is "six hundred forty-four billion, four hundred twenty-two million, two hundred twenty-four thousand, four hundred forty-six".