856838123 has 2 divisors, whose sum is σ = 856838124. Its totient is φ = 856838122.

The previous prime is 856838107. The next prime is 856838137. The reversal of 856838123 is 321838658.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 856838123 - 2⁴ = 856838107 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (856838173) 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, 428419061 + 428419062.

It is an arithmetic number, because the mean of its divisors is an integer number (428419062).

Almost surely, 2^856838123 is an apocalyptic number.

856838123 is a deficient number, since it is larger than the sum of its proper divisors (1).

856838123 is an equidigital number, since it uses as much as digits as its factorization.

856838123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 276480, while the sum is 44.

The square root of 856838123 is about 29271.7973995448. The cubic root of 856838123 is about 949.8016660754.

The spelling of 856838123 in words is "eight hundred fifty-six million, eight hundred thirty-eight thousand, one hundred twenty-three".