644484446 has 8 divisors (see below), whose sum is σ = 1017607080. Its totient is φ = 305282088.

The previous prime is 644484439. The next prime is 644484461.

644484446 is nontrivially palindromic in base 10.

644484446 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 super-2 number, since 2×644484446² = 830720402271853832, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 644484397 and 644484406.

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, 8480021 + ... + 8480096.

It is an arithmetic number, because the mean of its divisors is an integer number (127200885).

Almost surely, 2^644484446 is an apocalyptic number.

644484446 is a deficient number, since it is larger than the sum of its proper divisors (373122634).

644484446 is a wasteful number, since it uses less digits than its factorization.

644484446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16960138.

The product of its digits is 1179648, while the sum is 44.

The square root of 644484446 is about 25386.6982098894. The cubic root of 644484446 is about 863.7819942870.

The spelling of 644484446 in words is "six hundred forty-four million, four hundred eighty-four thousand, four hundred forty-six".