18036172800 has 360 divisors, whose sum is σ = 66817500750. Its totient is φ = 4808540160.

The previous prime is 18036172793. The next prime is 18036172801. The reversal of 18036172800 is 827163081.

18036172800 is a `hidden beast` number, since 18 + 0 + 3 + 617 + 28 + 0 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 7817389056 + 10218783744 = 88416^2 + 101088^2 .

It is a tau number, because it is divible by the number of its divisors (360).

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

It is not an unprimeable number, because it can be changed into a prime (18036172801) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 4145026 + ... + 4149374.

Almost surely, 2^18036172800 is an apocalyptic number.

18036172800 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 18036172800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33408750375).

18036172800 is an abundant number, since it is smaller than the sum of its proper divisors (48781327950).

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

18036172800 is an equidigital number, since it uses as much as digits as its factorization.

18036172800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4393 (or 4359 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The spelling of 18036172800 in words is "eighteen billion, thirty-six million, one hundred seventy-two thousand, eight hundred".