9817979919823 has 2 divisors, whose sum is σ = 9817979919824. Its totient is φ = 9817979919822.

The previous prime is 9817979919773. The next prime is 9817979919857. The reversal of 9817979919823 is 3289199797189.

It is a strong prime.

It is an emirp because it is prime and its reverse (3289199797189) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9817979919823 - 2¹⁷ = 9817979788751 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9817979919893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4908989959911 + 4908989959912.

It is an arithmetic number, because the mean of its divisors is an integer number (4908989959912).

Almost surely, 2^{9817979919823} is an apocalyptic number.

9817979919823 is a deficient number, since it is larger than the sum of its proper divisors (1).

9817979919823 is an equidigital number, since it uses as much as digits as its factorization.

9817979919823 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1111065984, while the sum is 82.

The spelling of 9817979919823 in words is "nine trillion, eight hundred seventeen billion, nine hundred seventy-nine million, nine hundred nineteen thousand, eight hundred twenty-three".