18889109 has 4 divisors (see below), whose sum is σ = 19171104. Its totient is φ = 18607116.

The previous prime is 18889099. The next prime is 18889133. The reversal of 18889109 is 90198881.

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 an emirpimes, since its reverse is a distinct semiprime: 90198881 = 797 ⋅113173.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18889109 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18889109.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18889009) 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, 140897 + ... + 141030.

It is an arithmetic number, because the mean of its divisors is an integer number (4792776).

Almost surely, 2^18889109 is an apocalyptic number.

It is an amenable number.

18889109 is a deficient number, since it is larger than the sum of its proper divisors (281995).

18889109 is an equidigital number, since it uses as much as digits as its factorization.

18889109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281994.

The product of its (nonzero) digits is 41472, while the sum is 44.

The square root of 18889109 is about 4346.1602593554. The cubic root of 18889109 is about 266.3200258110.

The spelling of 18889109 in words is "eighteen million, eight hundred eighty-nine thousand, one hundred nine".