646441361 has 2 divisors, whose sum is σ = 646441362. Its totient is φ = 646441360.

The previous prime is 646441331. The next prime is 646441363. The reversal of 646441361 is 163144646.

It is a happy number.

646441361 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 can be written as a sum of positive squares in only one way, i.e., 334707025 + 311734336 = 18295^2 + 17656^2 .

It is a cyclic number.

It is not a de Polignac number, because 646441361 - 2¹⁸ = 646179217 is a prime.

Together with 646441363, 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 (646441363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323220680 + 323220681.

It is an arithmetic number, because the mean of its divisors is an integer number (323220681).

Almost surely, 2^646441361 is an apocalyptic number.

It is an amenable number.

646441361 is a deficient number, since it is larger than the sum of its proper divisors (1).

646441361 is an equidigital number, since it uses as much as digits as its factorization.

646441361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 35.

The square root of 646441361 is about 25425.2111299002. The cubic root of 646441361 is about 864.6553745381.

The spelling of 646441361 in words is "six hundred forty-six million, four hundred forty-one thousand, three hundred sixty-one".