18808019 has 4 divisors (see below), whose sum is σ = 18831696. Its totient is φ = 18784344.

The previous prime is 18808007. The next prime is 18808021. The reversal of 18808019 is 91080881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91080881 = 157 ⋅580133.

It is a cyclic number.

It is not a de Polignac number, because 18808019 - 2⁴ = 18808003 is a prime.

It is a super-2 number, since 2×18808019² = 707483157408722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18808019.

It is not an unprimeable number, because it can be changed into a prime (18808619) 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, 10604 + ... + 12249.

It is an arithmetic number, because the mean of its divisors is an integer number (4707924).

Almost surely, 2^18808019 is an apocalyptic number.

18808019 is a deficient number, since it is larger than the sum of its proper divisors (23677).

18808019 is an equidigital number, since it uses as much as digits as its factorization.

18808019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23676.

The product of its (nonzero) digits is 4608, while the sum is 35.

The square root of 18808019 is about 4336.8213013681. The cubic root of 18808019 is about 265.9383796435.

The spelling of 18808019 in words is "eighteen million, eight hundred eight thousand, nineteen".