18238541 has 4 divisors (see below), whose sum is σ = 18317052. Its totient is φ = 18160032.

The previous prime is 18238523. The next prime is 18238553. The reversal of 18238541 is 14583281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14583281 = 2473 ⋅5897.

It can be written as a sum of positive squares in 2 ways, for example, as 1510441 + 16728100 = 1229^2 + 4090^2 .

It is a cyclic number.

It is not a de Polignac number, because 18238541 - 2¹⁴ = 18222157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 18238498 and 18238507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18232541) 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, 38906 + ... + 39371.

It is an arithmetic number, because the mean of its divisors is an integer number (4579263).

Almost surely, 2^18238541 is an apocalyptic number.

It is an amenable number.

18238541 is a deficient number, since it is larger than the sum of its proper divisors (78511).

18238541 is an equidigital number, since it uses as much as digits as its factorization.

18238541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78510.

The product of its digits is 7680, while the sum is 32.

The square root of 18238541 is about 4270.6604875593. The cubic root of 18238541 is about 263.2267558173.

The spelling of 18238541 in words is "eighteen million, two hundred thirty-eight thousand, five hundred forty-one".