644674323 has 24 divisors (see below), whose sum is σ = 915346288. Its totient is φ = 403508736.

The previous prime is 644674309. The next prime is 644674333. The reversal of 644674323 is 323476446.

It is not a de Polignac number, because 644674323 - 2⁴ = 644674307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (644674333) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 530865 + ... + 532077.

Almost surely, 2^644674323 is an apocalyptic number.

644674323 is a deficient number, since it is larger than the sum of its proper divisors (270671965).

644674323 is a wasteful number, since it uses less digits than its factorization.

644674323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1863 (or 1846 counting only the distinct ones).

The product of its digits is 290304, while the sum is 39.

The square root of 644674323 is about 25390.4376291548. The cubic root of 644674323 is about 863.8668146579.

The spelling of 644674323 in words is "six hundred forty-four million, six hundred seventy-four thousand, three hundred twenty-three".