644383446 has 32 divisors (see below), whose sum is σ = 1473739008. Its totient is φ = 184001760.

The previous prime is 644383357. The next prime is 644383447.

644383446 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 644383398 and 644383407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644383447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92961 + ... + 99651.

It is an arithmetic number, because the mean of its divisors is an integer number (46054344).

Almost surely, 2^644383446 is an apocalyptic number.

644383446 is an abundant number, since it is smaller than the sum of its proper divisors (829355562).

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

644383446 is a wasteful number, since it uses less digits than its factorization.

644383446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8996.

The product of its digits is 663552, while the sum is 42.

The square root of 644383446 is about 25384.7089012263. The cubic root of 644383446 is about 863.7368695676.

The spelling of 644383446 in words is "six hundred forty-four million, three hundred eighty-three thousand, four hundred forty-six".