18238320 has 120 divisors (see below), whose sum is σ = 62268336. Its totient is φ = 4783104.

The previous prime is 18238301. The next prime is 18238349. The reversal of 18238320 is 2383281.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52387 + ... + 52733.

Almost surely, 2^18238320 is an apocalyptic number.

18238320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18238320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31134168).

18238320 is an abundant number, since it is smaller than the sum of its proper divisors (44030016).

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

18238320 is a wasteful number, since it uses less digits than its factorization.

18238320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439 (or 430 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 18238320 is about 4270.6346132630. The cubic root of 18238320 is about 263.2256926228.

The spelling of 18238320 in words is "eighteen million, two hundred thirty-eight thousand, three hundred twenty".