644424263339 has 2 divisors, whose sum is σ = 644424263340. Its totient is φ = 644424263338.

The previous prime is 644424263321. The next prime is 644424263341. The reversal of 644424263339 is 933362424446.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 644424263339 - 2²⁴ = 644407486123 is a prime.

Together with 644424263341, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (644424263039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322212131669 + 322212131670.

It is an arithmetic number, because the mean of its divisors is an integer number (322212131670).

Almost surely, 2^644424263339 is an apocalyptic number.

644424263339 is a deficient number, since it is larger than the sum of its proper divisors (1).

644424263339 is an equidigital number, since it uses as much as digits as its factorization.

644424263339 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8957952, while the sum is 50.

The spelling of 644424263339 in words is "six hundred forty-four billion, four hundred twenty-four million, two hundred sixty-three thousand, three hundred thirty-nine".