644303104 has 36 divisors (see below), whose sum is σ = 1301627376. Its totient is φ = 318259712.

The previous prime is 644303087. The next prime is 644303123. The reversal of 644303104 is 401303446.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6087 + ... + 36409.

It is an arithmetic number, because the mean of its divisors is an integer number (36156316).

Almost surely, 2^644303104 is an apocalyptic number.

644303104 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644303104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (650813688).

644303104 is an abundant number, since it is smaller than the sum of its proper divisors (657324272).

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

644303104 is an equidigital number, since it uses as much as digits as its factorization.

644303104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30422 (or 30408 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 644303104 is about 25383.1263637874. The cubic root of 644303104 is about 863.7009710498.

The spelling of 644303104 in words is "six hundred forty-four million, three hundred three thousand, one hundred four".