18816840 has 256 divisors, whose sum is σ = 76032000. Its totient is φ = 4043520.

The previous prime is 18816839. The next prime is 18816851. The reversal of 18816840 is 4861881.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18816795 and 18816804.

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 63 ways as a sum of consecutive naturals, for example, 143575 + ... + 143705.

It is an arithmetic number, because the mean of its divisors is an integer number (297000).

Almost surely, 2^18816840 is an apocalyptic number.

18816840 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 18816840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38016000).

18816840 is an abundant number, since it is smaller than the sum of its proper divisors (57215160).

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

18816840 is a wasteful number, since it uses less digits than its factorization.

18816840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177 (or 167 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 36.

The square root of 18816840 is about 4337.8381712554. The cubic root of 18816840 is about 265.9799483632.

The spelling of 18816840 in words is "eighteen million, eight hundred sixteen thousand, eight hundred forty".