19998113 has 4 divisors (see below), whose sum is σ = 20007168. Its totient is φ = 19989060.

The previous prime is 19998047. The next prime is 19998149. The reversal of 19998113 is 31189991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 19998113 - 2²⁰ = 18949537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19998163) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1208 + ... + 6438.

It is an arithmetic number, because the mean of its divisors is an integer number (5001792).

Almost surely, 2^19998113 is an apocalyptic number.

It is an amenable number.

19998113 is a deficient number, since it is larger than the sum of its proper divisors (9055).

19998113 is an equidigital number, since it uses as much as digits as its factorization.

19998113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9054.

The product of its digits is 17496, while the sum is 41.

The square root of 19998113 is about 4471.9249770093. The cubic root of 19998113 is about 271.4332245476.

The spelling of 19998113 in words is "nineteen million, nine hundred ninety-eight thousand, one hundred thirteen".