18418139 has 4 divisors (see below), whose sum is σ = 18651360. Its totient is φ = 18184920.

The previous prime is 18418133. The next prime is 18418159. The reversal of 18418139 is 93181481.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93181481 = 953 ⋅97777.

It is a cyclic number.

It is not a de Polignac number, because 18418139 - 2¹⁶ = 18352603 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18418099 and 18418108.

It is not an unprimeable number, because it can be changed into a prime (18418133) 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, 116492 + ... + 116649.

It is an arithmetic number, because the mean of its divisors is an integer number (4662840).

Almost surely, 2^18418139 is an apocalyptic number.

18418139 is a deficient number, since it is larger than the sum of its proper divisors (233221).

18418139 is an equidigital number, since it uses as much as digits as its factorization.

18418139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233220.

The product of its digits is 6912, while the sum is 35.

The square root of 18418139 is about 4291.6359351651. The cubic root of 18418139 is about 264.0879480091.

The spelling of 18418139 in words is "eighteen million, four hundred eighteen thousand, one hundred thirty-nine".