18889189 has 6 divisors (see below), whose sum is σ = 20762630. Its totient is φ = 17171880.

The previous prime is 18889183. The next prime is 18889201. The reversal of 18889189 is 98198881.

It can be written as a sum of positive squares in only one way, i.e., 17288964 + 1600225 = 4158^2 + 1265^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18889189 is a prime.

It is a super-2 number, since 2×18889189² = 713602922155442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18889183) 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 5 ways as a sum of consecutive naturals, for example, 77934 + ... + 78175.

Almost surely, 2^18889189 is an apocalyptic number.

It is an amenable number.

18889189 is a deficient number, since it is larger than the sum of its proper divisors (1873441).

18889189 is a wasteful number, since it uses less digits than its factorization.

18889189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156131 (or 156120 counting only the distinct ones).

The product of its digits is 331776, while the sum is 52.

The square root of 18889189 is about 4346.1694628719. The cubic root of 18889189 is about 266.3204017873.

The spelling of 18889189 in words is "eighteen million, eight hundred eighty-nine thousand, one hundred eighty-nine".