18663120 has 270 divisors, whose sum is σ = 76217778. Its totient is φ = 4080384.

The previous prime is 18663119. The next prime is 18663121. The reversal of 18663120 is 2136681.

18663120 is a `hidden beast` number, since 1 + 8 + 6 + 631 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (18663119) and next prime (18663121).

It can be written as a sum of positive squares in only one way, i.e., 14930496 + 3732624 = 3864^2 + 1932^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18663121) by changing a digit.

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 53 ways as a sum of consecutive naturals, for example, 811429 + ... + 811451.

Almost surely, 2^18663120 is an apocalyptic number.

18663120 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 18663120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38108889).

18663120 is an abundant number, since it is smaller than the sum of its proper divisors (57554658).

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

18663120 is a wasteful number, since it uses less digits than its factorization.

18663120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 18663120 is about 4320.0833325296. The cubic root of 18663120 is about 265.2536789985.

The spelling of 18663120 in words is "eighteen million, six hundred sixty-three thousand, one hundred twenty".