644484255 has 16 divisors (see below), whose sum is σ = 1066733280. Its totient is φ = 331872128.

The previous prime is 644484221. The next prime is 644484259. The reversal of 644484255 is 552484446.

644484255 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 644484255 - 2¹¹ = 644482207 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644484259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 740352 + ... + 741221.

It is an arithmetic number, because the mean of its divisors is an integer number (66670830).

Almost surely, 2^644484255 is an apocalyptic number.

644484255 is a deficient number, since it is larger than the sum of its proper divisors (422249025).

644484255 is a wasteful number, since it uses less digits than its factorization.

644484255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1481610.

The product of its digits is 614400, while the sum is 42.

The square root of 644484255 is about 25386.6944480765. The cubic root of 644484255 is about 863.7819089565.

The spelling of 644484255 in words is "six hundred forty-four million, four hundred eighty-four thousand, two hundred fifty-five".