644001334 has 8 divisors (see below), whose sum is σ = 1008002160. Its totient is φ = 308000616.

The previous prime is 644001299. The next prime is 644001341. The reversal of 644001334 is 433100446.

It is a happy number.

644001334 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 644001299 and 644001308.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6999969 + ... + 7000060.

It is an arithmetic number, because the mean of its divisors is an integer number (126000270).

Almost surely, 2^644001334 is an apocalyptic number.

644001334 is a deficient number, since it is larger than the sum of its proper divisors (364000826).

644001334 is a wasteful number, since it uses less digits than its factorization.

644001334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14000054.

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

The square root of 644001334 is about 25377.1813643675. The cubic root of 644001334 is about 863.5661071209.

The spelling of 644001334 in words is "six hundred forty-four million, one thousand, three hundred thirty-four".