18224640 has 240 divisors, whose sum is σ = 72772128. Its totient is φ = 4128768.

The previous prime is 18224639. The next prime is 18224653. The reversal of 18224640 is 4642281.

18224640 is a `hidden beast` number, since 18 + 2 + 2 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

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, 161224 + ... + 161336.

Almost surely, 2^18224640 is an apocalyptic number.

18224640 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 18224640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36386064).

18224640 is an abundant number, since it is smaller than the sum of its proper divisors (54547488).

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

18224640 is a wasteful number, since it uses less digits than its factorization.

18224640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 18224640 is about 4269.0326773170. The cubic root of 18224640 is about 263.1598636765.

The spelling of 18224640 in words is "eighteen million, two hundred twenty-four thousand, six hundred forty".