2156656838123 has 2 divisors, whose sum is σ = 2156656838124. Its totient is φ = 2156656838122.

The previous prime is 2156656838107. The next prime is 2156656838173. The reversal of 2156656838123 is 3218386566512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2156656838123 - 2⁴ = 2156656838107 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (2156656838173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078328419061 + 1078328419062.

It is an arithmetic number, because the mean of its divisors is an integer number (1078328419062).

Almost surely, 2^{2156656838123} is an apocalyptic number.

2156656838123 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156656838123 is an equidigital number, since it uses as much as digits as its factorization.

2156656838123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12441600, while the sum is 56.

The spelling of 2156656838123 in words is "two trillion, one hundred fifty-six billion, six hundred fifty-six million, eight hundred thirty-eight thousand, one hundred twenty-three".