644222446 has 16 divisors (see below), whose sum is σ = 1169345376. Its totient is φ = 259854336.

The previous prime is 644222441. The next prime is 644222471.

644222446 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644222441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1353171 + ... + 1353646.

It is an arithmetic number, because the mean of its divisors is an integer number (73084086).

Almost surely, 2^644222446 is an apocalyptic number.

644222446 is a deficient number, since it is larger than the sum of its proper divisors (525122930).

644222446 is a wasteful number, since it uses less digits than its factorization.

644222446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2706843.

The product of its digits is 73728, while the sum is 34.

The square root of 644222446 is about 25381.5375026810. The cubic root of 644222446 is about 863.6649283345.

The spelling of 644222446 in words is "six hundred forty-four million, two hundred twenty-two thousand, four hundred forty-six".