644244446 has 8 divisors (see below), whose sum is σ = 967103280. Its totient is φ = 321876688.

The previous prime is 644244443. The next prime is 644244493. The reversal of 644244446 is 644442446.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644244443) 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 3 ways as a sum of consecutive naturals, for example, 119471 + ... + 124746.

It is an arithmetic number, because the mean of its divisors is an integer number (120887910).

Almost surely, 2^644244446 is an apocalyptic number.

644244446 is a deficient number, since it is larger than the sum of its proper divisors (322858834).

644244446 is a wasteful number, since it uses less digits than its factorization.

644244446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245538.

The product of its digits is 294912, while the sum is 38.

The square root of 644244446 is about 25381.9708848623. The cubic root of 644244446 is about 863.6747595205.

The spelling of 644244446 in words is "six hundred forty-four million, two hundred forty-four thousand, four hundred forty-six".