18718889 has 8 divisors (see below), whose sum is σ = 21890880. Its totient is φ = 15671376.

The previous prime is 18718883. The next prime is 18718927. The reversal of 18718889 is 98881781.

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

It is not a de Polignac number, because 18718889 - 2⁴ = 18718873 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 (18718883) 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, 30794 + ... + 31395.

It is an arithmetic number, because the mean of its divisors is an integer number (2736360).

Almost surely, 2^18718889 is an apocalyptic number.

It is an amenable number.

18718889 is a deficient number, since it is larger than the sum of its proper divisors (3171991).

18718889 is an equidigital number, since it uses as much as digits as its factorization.

18718889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62239.

The product of its digits is 258048, while the sum is 50.

The square root of 18718889 is about 4326.5331386689. The cubic root of 18718889 is about 265.5176259721.

The spelling of 18718889 in words is "eighteen million, seven hundred eighteen thousand, eight hundred eighty-nine".