18938238 has 32 divisors (see below), whose sum is σ = 43752960. Its totient is φ = 5400960.

The previous prime is 18938209. The next prime is 18938239. The reversal of 18938238 is 83283981.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18938238.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18938239) 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, 7318 + ... + 9561.

It is an arithmetic number, because the mean of its divisors is an integer number (1367280).

Almost surely, 2^18938238 is an apocalyptic number.

18938238 is an abundant number, since it is smaller than the sum of its proper divisors (24814722).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18938238 is a wasteful number, since it uses less digits than its factorization.

18938238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16912.

The product of its digits is 82944, while the sum is 42.

The square root of 18938238 is about 4351.8085895407. The cubic root of 18938238 is about 266.5507179947.

It can be divided in two parts, 189382 and 38, that added together give a triangular number (189420 = T₆₁₅).

The spelling of 18938238 in words is "eighteen million, nine hundred thirty-eight thousand, two hundred thirty-eight".