19998163 has 2 divisors, whose sum is σ = 19998164. Its totient is φ = 19998162.

The previous prime is 19998161. The next prime is 19998169. The reversal of 19998163 is 36189991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19998163 - 2¹ = 19998161 is a prime.

Together with 19998161, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (19998161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9999081 + 9999082.

It is an arithmetic number, because the mean of its divisors is an integer number (9999082).

Almost surely, 2^19998163 is an apocalyptic number.

19998163 is a deficient number, since it is larger than the sum of its proper divisors (1).

19998163 is an equidigital number, since it uses as much as digits as its factorization.

19998163 is an evil number, because the sum of its binary digits is even.

The product of its digits is 104976, while the sum is 46.

The square root of 19998163 is about 4471.9305674395. The cubic root of 19998163 is about 271.4334507631.

The spelling of 19998163 in words is "nineteen million, nine hundred ninety-eight thousand, one hundred sixty-three".