18538161 has 16 divisors (see below), whose sum is σ = 25958016. Its totient is φ = 11745536.

The previous prime is 18538159. The next prime is 18538183. The reversal of 18538161 is 16183581.

It is a cyclic number.

It is not a de Polignac number, because 18538161 - 2¹ = 18538159 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18538111) 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, 11161 + ... + 12713.

It is an arithmetic number, because the mean of its divisors is an integer number (1622376).

Almost surely, 2^18538161 is an apocalyptic number.

It is an amenable number.

18538161 is a deficient number, since it is larger than the sum of its proper divisors (7419855).

18538161 is a wasteful number, since it uses less digits than its factorization.

18538161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1752.

The product of its digits is 5760, while the sum is 33.

The square root of 18538161 is about 4305.5964743575. The cubic root of 18538161 is about 264.6603504285.

The spelling of 18538161 in words is "eighteen million, five hundred thirty-eight thousand, one hundred sixty-one".