18128109238 has 4 divisors (see below), whose sum is σ = 27192163860. Its totient is φ = 9064054618.

The previous prime is 18128109193. The next prime is 18128109253. The reversal of 18128109238 is 83290182181.

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: 83290182181 = 19 ⋅4383693799.

It is a junction number, because it is equal to n+sod(n) for n = 18128109194 and 18128109203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4532027308 + ... + 4532027311.

It is an arithmetic number, because the mean of its divisors is an integer number (6798040965).

Almost surely, 2^18128109238 is an apocalyptic number.

18128109238 is a deficient number, since it is larger than the sum of its proper divisors (9064054622).

18128109238 is an equidigital number, since it uses as much as digits as its factorization.

18128109238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9064054621.

The product of its (nonzero) digits is 55296, while the sum is 43.

The spelling of 18128109238 in words is "eighteen billion, one hundred twenty-eight million, one hundred nine thousand, two hundred thirty-eight".