646397123 has 2 divisors, whose sum is σ = 646397124. Its totient is φ = 646397122.

The previous prime is 646397093. The next prime is 646397149. The reversal of 646397123 is 321793646.

646397123 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 646397123 - 2²⁸ = 377961667 is a prime.

It is not a weakly prime, because it can be changed into another prime (646397183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323198561 + 323198562.

It is an arithmetic number, because the mean of its divisors is an integer number (323198562).

Almost surely, 2^646397123 is an apocalyptic number.

646397123 is a deficient number, since it is larger than the sum of its proper divisors (1).

646397123 is an equidigital number, since it uses as much as digits as its factorization.

646397123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 41.

The square root of 646397123 is about 25424.3411517388. The cubic root of 646397123 is about 864.6356503995.

The spelling of 646397123 in words is "six hundred forty-six million, three hundred ninety-seven thousand, one hundred twenty-three".