18121824 has 144 divisors (see below), whose sum is σ = 60147360. Its totient is φ = 5068800.

The previous prime is 18121811. The next prime is 18121843. The reversal of 18121824 is 42812181.

It is a tau number, because it is divible by the number of its divisors (144).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 179374 + ... + 179474.

It is an arithmetic number, because the mean of its divisors is an integer number (417690).

Almost surely, 2^18121824 is an apocalyptic number.

18121824 is a gapful number since it is divisible by the number (14) 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 18121824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30073680).

18121824 is an abundant number, since it is smaller than the sum of its proper divisors (42025536).

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

18121824 is a wasteful number, since it uses less digits than its factorization.

18121824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 202 counting only the distinct ones).

The product of its digits is 1024, while the sum is 27.

The square root of 18121824 is about 4256.9735728567. The cubic root of 18121824 is about 262.6640498364.

The spelling of 18121824 in words is "eighteen million, one hundred twenty-one thousand, eight hundred twenty-four".