18423889 has 16 divisors (see below), whose sum is σ = 20998656. Its totient is φ = 16012800.

The previous prime is 18423841. The next prime is 18423893. The reversal of 18423889 is 98832481.

It is a cyclic number.

It is not a de Polignac number, because 18423889 - 2¹¹ = 18421841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18423829) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32799 + ... + 33355.

It is an arithmetic number, because the mean of its divisors is an integer number (1312416).

Almost surely, 2^18423889 is an apocalyptic number.

It is an amenable number.

18423889 is a deficient number, since it is larger than the sum of its proper divisors (2574767).

18423889 is a wasteful number, since it uses less digits than its factorization.

18423889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696.

The product of its digits is 110592, while the sum is 43.

The square root of 18423889 is about 4292.3057905979. The cubic root of 18423889 is about 264.1154272187.

The spelling of 18423889 in words is "eighteen million, four hundred twenty-three thousand, eight hundred eighty-nine".