19998057 has 8 divisors (see below), whose sum is σ = 27101440. Its totient is φ = 13113360.

The previous prime is 19998047. The next prime is 19998149. The reversal of 19998057 is 75089991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 19998057 - 2⁶ = 19997993 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19997997 and 19998015.

It is not an unprimeable number, because it can be changed into a prime (19998047) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54457 + ... + 54822.

It is an arithmetic number, because the mean of its divisors is an integer number (3387680).

Almost surely, 2^19998057 is an apocalyptic number.

It is an amenable number.

19998057 is a deficient number, since it is larger than the sum of its proper divisors (7103383).

19998057 is a wasteful number, since it uses less digits than its factorization.

19998057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109343.

The product of its (nonzero) digits is 204120, while the sum is 48.

The square root of 19998057 is about 4471.9187157192. The cubic root of 19998057 is about 271.4329711858.

The spelling of 19998057 in words is "nineteen million, nine hundred ninety-eight thousand, fifty-seven".