18238740 has 96 divisors (see below), whose sum is σ = 55977600. Its totient is φ = 4409856.

The previous prime is 18238711. The next prime is 18238771. The reversal of 18238740 is 4783281.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 52086 + ... + 52434.

It is an arithmetic number, because the mean of its divisors is an integer number (583100).

Almost surely, 2^18238740 is an apocalyptic number.

18238740 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 18238740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27988800).

18238740 is an abundant number, since it is smaller than the sum of its proper divisors (37738860).

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

18238740 is a wasteful number, since it uses less digits than its factorization.

18238740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441 (or 439 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 18238740 is about 4270.6837859996. The cubic root of 18238740 is about 263.2277131661.

The spelling of 18238740 in words is "eighteen million, two hundred thirty-eight thousand, seven hundred forty".