646403323 has 2 divisors, whose sum is σ = 646403324. Its totient is φ = 646403322.

The previous prime is 646403321. The next prime is 646403327. The reversal of 646403323 is 323304646.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 646403323 - 2¹ = 646403321 is a prime.

Together with 646403321, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (646403321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323201661 + 323201662.

It is an arithmetic number, because the mean of its divisors is an integer number (323201662).

Almost surely, 2^646403323 is an apocalyptic number.

646403323 is a deficient number, since it is larger than the sum of its proper divisors (1).

646403323 is an equidigital number, since it uses as much as digits as its factorization.

646403323 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 31.

The square root of 646403323 is about 25424.4630818430. The cubic root of 646403323 is about 864.6384148115.

Adding to 646403323 its reverse (323304646), we get a palindrome (969707969).

The spelling of 646403323 in words is "six hundred forty-six million, four hundred three thousand, three hundred twenty-three".