18612238 has 4 divisors (see below), whose sum is σ = 27918360. Its totient is φ = 9306118.

The previous prime is 18612233. The next prime is 18612257. The reversal of 18612238 is 83221681.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18612233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4653058 + ... + 4653061.

It is an arithmetic number, because the mean of its divisors is an integer number (6979590).

Almost surely, 2^18612238 is an apocalyptic number.

18612238 is a deficient number, since it is larger than the sum of its proper divisors (9306122).

18612238 is an equidigital number, since it uses as much as digits as its factorization.

18612238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9306121.

The product of its digits is 4608, while the sum is 31.

The square root of 18612238 is about 4314.1903064190. The cubic root of 18612238 is about 265.0124024099.

The spelling of 18612238 in words is "eighteen million, six hundred twelve thousand, two hundred thirty-eight".