644613367 has 2 divisors, whose sum is σ = 644613368. Its totient is φ = 644613366.

The previous prime is 644613257. The next prime is 644613419. The reversal of 644613367 is 763316446.

It is a happy number.

644613367 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 644613367 - 2⁷ = 644613239 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644613467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322306683 + 322306684.

It is an arithmetic number, because the mean of its divisors is an integer number (322306684).

Almost surely, 2^644613367 is an apocalyptic number.

644613367 is a deficient number, since it is larger than the sum of its proper divisors (1).

644613367 is an equidigital number, since it uses as much as digits as its factorization.

644613367 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 40.

The square root of 644613367 is about 25389.2372276128. The cubic root of 644613367 is about 863.8395866848.

The spelling of 644613367 in words is "six hundred forty-four million, six hundred thirteen thousand, three hundred sixty-seven".