18423871 has 4 divisors (see below), whose sum is σ = 18736200. Its totient is φ = 18111544.

The previous prime is 18423841. The next prime is 18423893. The reversal of 18423871 is 17832481.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17832481 = 673 ⋅26497.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18423871 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 (18423841) 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 3 ways as a sum of consecutive naturals, for example, 156076 + ... + 156193.

It is an arithmetic number, because the mean of its divisors is an integer number (4684050).

Almost surely, 2^18423871 is an apocalyptic number.

18423871 is a deficient number, since it is larger than the sum of its proper divisors (312329).

18423871 is an equidigital number, since it uses as much as digits as its factorization.

18423871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312328.

The product of its digits is 10752, while the sum is 34.

The square root of 18423871 is about 4292.3036938222. The cubic root of 18423871 is about 264.1153412057.

The spelling of 18423871 in words is "eighteen million, four hundred twenty-three thousand, eight hundred seventy-one".