18943238 has 4 divisors (see below), whose sum is σ = 28414860. Its totient is φ = 9471618.

The previous prime is 18943231. The next prime is 18943241. The reversal of 18943238 is 83234981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83234981 = 7459 ⋅11159.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18943231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4735808 + ... + 4735811.

It is an arithmetic number, because the mean of its divisors is an integer number (7103715).

Almost surely, 2^18943238 is an apocalyptic number.

18943238 is a deficient number, since it is larger than the sum of its proper divisors (9471622).

18943238 is an equidigital number, since it uses as much as digits as its factorization.

18943238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9471621.

The product of its digits is 41472, while the sum is 38.

The square root of 18943238 is about 4352.3830254241. The cubic root of 18943238 is about 266.5741738255.

The spelling of 18943238 in words is "eighteen million, nine hundred forty-three thousand, two hundred thirty-eight".