644227675 has 48 divisors (see below), whose sum is σ = 988825600. Its totient is φ = 405440640.

The previous prime is 644227651. The next prime is 644227679. The reversal of 644227675 is 576722446.

It is not a de Polignac number, because 644227675 - 2⁵ = 644227643 is a prime.

It is not an unprimeable number, because it can be changed into a prime (644227679) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 452014 + ... + 453436.

Almost surely, 2^644227675 is an apocalyptic number.

644227675 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

644227675 is a deficient number, since it is larger than the sum of its proper divisors (344597925).

644227675 is a wasteful number, since it uses less digits than its factorization.

644227675 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1652 (or 1647 counting only the distinct ones).

The product of its digits is 564480, while the sum is 43.

The square root of 644227675 is about 25381.6405104162. The cubic root of 644227675 is about 863.6672650489.

The spelling of 644227675 in words is "six hundred forty-four million, two hundred twenty-seven thousand, six hundred seventy-five".