644074334 has 16 divisors (see below), whose sum is σ = 972373248. Its totient is φ = 319957272.

The previous prime is 644074307. The next prime is 644074337. The reversal of 644074334 is 433470446.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 644074294 and 644074303.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644074337) 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 7 ways as a sum of consecutive naturals, for example, 211547 + ... + 214569.

It is an arithmetic number, because the mean of its divisors is an integer number (60773328).

Almost surely, 2^644074334 is an apocalyptic number.

644074334 is a deficient number, since it is larger than the sum of its proper divisors (328298914).

644074334 is a wasteful number, since it uses less digits than its factorization.

644074334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3679.

The product of its (nonzero) digits is 96768, while the sum is 35.

The square root of 644074334 is about 25378.6196236123. The cubic root of 644074334 is about 863.5987353887.

The spelling of 644074334 in words is "six hundred forty-four million, seventy-four thousand, three hundred thirty-four".