18994338 has 144 divisors (see below), whose sum is σ = 52284960. Its totient is φ = 5132160.

The previous prime is 18994337. The next prime is 18994361. The reversal of 18994338 is 83349981.

It is a junction number, because it is equal to n+sod(n) for n = 18994293 and 18994302.

It is not an unprimeable number, because it can be changed into a prime (18994337) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 999693 + ... + 999711.

It is an arithmetic number, because the mean of its divisors is an integer number (363090).

Almost surely, 2^18994338 is an apocalyptic number.

18994338 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18994338, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26142480).

18994338 is an abundant number, since it is smaller than the sum of its proper divisors (33290622).

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

18994338 is a wasteful number, since it uses less digits than its factorization.

18994338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75 (or 52 counting only the distinct ones).

The product of its digits is 186624, while the sum is 45.

The square root of 18994338 is about 4358.2494192049. The cubic root of 18994338 is about 266.8136561158.

It can be divided in two parts, 189943 and 38, that added together give a palindrome (189981).

The spelling of 18994338 in words is "eighteen million, nine hundred ninety-four thousand, three hundred thirty-eight".