644080446 has 24 divisors (see below), whose sum is σ = 1396745064. Its totient is φ = 214503120.

The previous prime is 644080441. The next prime is 644080471.

644080446 is a `hidden beast` number, since 644 + 0 + 8 + 0 + 4 + 4 + 6 = 666.

644080446 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 644080446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644080441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5800 + ... + 36356.

It is an arithmetic number, because the mean of its divisors is an integer number (58197711).

Almost surely, 2^644080446 is an apocalyptic number.

644080446 is an abundant number, since it is smaller than the sum of its proper divisors (752664618).

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

644080446 is a wasteful number, since it uses less digits than its factorization.

644080446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31736 (or 31733 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 36.

The square root of 644080446 is about 25378.7400396474. The cubic root of 644080446 is about 863.6014671121.

The spelling of 644080446 in words is "six hundred forty-four million, eighty thousand, four hundred forty-six".