18934398 has 80 divisors (see below), whose sum is σ = 49484160. Its totient is φ = 5299344.

The previous prime is 18934381. The next prime is 18934423. The reversal of 18934398 is 89343981.

It is a super-2 number, since 2×18934398² = 717022855244808, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 66765 + ... + 67047.

It is an arithmetic number, because the mean of its divisors is an integer number (618552).

Almost surely, 2^18934398 is an apocalyptic number.

18934398 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 18934398, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24742080).

18934398 is an abundant number, since it is smaller than the sum of its proper divisors (30549762).

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

18934398 is a wasteful number, since it uses less digits than its factorization.

18934398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363 (or 354 counting only the distinct ones).

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

The square root of 18934398 is about 4351.3673712984. The cubic root of 18934398 is about 266.5327011137.

The spelling of 18934398 in words is "eighteen million, nine hundred thirty-four thousand, three hundred ninety-eight".