644427088 has 20 divisors (see below), whose sum is σ = 1250142208. Its totient is φ = 321809760.

The previous prime is 644427071. The next prime is 644427089. The reversal of 644427088 is 880724446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644427089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11856 + ... + 37807.

Almost surely, 2^644427088 is an apocalyptic number.

It is an amenable number.

644427088 is a deficient number, since it is larger than the sum of its proper divisors (605715120).

644427088 is a wasteful number, since it uses less digits than its factorization.

644427088 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50482 (or 50476 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 43.

The square root of 644427088 is about 25385.5684986569. The cubic root of 644427088 is about 863.7563684927.

The spelling of 644427088 in words is "six hundred forty-four million, four hundred twenty-seven thousand, eighty-eight".