644550465239 has 2 divisors, whose sum is σ = 644550465240. Its totient is φ = 644550465238.

The previous prime is 644550465179. The next prime is 644550465241. The reversal of 644550465239 is 932564055446.

644550465239 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 644550465239 - 2⁸ = 644550464983 is a prime.

It is a super-2 number, since 2×644550465239² (a number of 24 digits) contains 22 as substring.

Together with 644550465241, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644550485239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322275232619 + 322275232620.

It is an arithmetic number, because the mean of its divisors is an integer number (322275232620).

Almost surely, 2^644550465239 is an apocalyptic number.

644550465239 is a deficient number, since it is larger than the sum of its proper divisors (1).

644550465239 is an equidigital number, since it uses as much as digits as its factorization.

644550465239 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552000, while the sum is 53.

The spelling of 644550465239 in words is "six hundred forty-four billion, five hundred fifty million, four hundred sixty-five thousand, two hundred thirty-nine".