18396840 has 192 divisors, whose sum is σ = 69713280. Its totient is φ = 3801600.

The previous prime is 18396821. The next prime is 18396863. The reversal of 18396840 is 4869381.

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 47 ways as a sum of consecutive naturals, for example, 101550 + ... + 101730.

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

Almost surely, 2^18396840 is an apocalyptic number.

18396840 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 18396840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34856640).

18396840 is an abundant number, since it is smaller than the sum of its proper divisors (51316440).

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

18396840 is a wasteful number, since it uses less digits than its factorization.

18396840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 18396840 is about 4289.1537626903. The cubic root of 18396840 is about 263.9861103804.

The spelling of 18396840 in words is "eighteen million, three hundred ninety-six thousand, eight hundred forty".