19993189 has 4 divisors (see below), whose sum is σ = 20418624. Its totient is φ = 19567756.

The previous prime is 19993157. The next prime is 19993201. The reversal of 19993189 is 98139991.

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.

It is a cyclic number.

It is not a de Polignac number, because 19993189 - 2⁵ = 19993157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19993489) 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, 212647 + ... + 212740.

It is an arithmetic number, because the mean of its divisors is an integer number (5104656).

Almost surely, 2^19993189 is an apocalyptic number.

It is an amenable number.

19993189 is a deficient number, since it is larger than the sum of its proper divisors (425435).

19993189 is an equidigital number, since it uses as much as digits as its factorization.

19993189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425434.

The product of its digits is 157464, while the sum is 49.

The square root of 19993189 is about 4471.3743972072. The cubic root of 19993189 is about 271.4109449970.

The spelling of 19993189 in words is "nineteen million, nine hundred ninety-three thousand, one hundred eighty-nine".