18006135840 has 1728 divisors, whose sum is σ = 87114787200. Its totient is φ = 3448811520.

The previous prime is 18006135817. The next prime is 18006135841. The reversal of 18006135840 is 4853160081.

18006135840 is a `hidden beast` number, since 18 + 0 + 0 + 61 + 3 + 584 + 0 = 666.

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 = 18006135795 and 18006135804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18006135841) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 486652302 + ... + 486652338.

It is an arithmetic number, because the mean of its divisors is an integer number (50413650).

Almost surely, 2^18006135840 is an apocalyptic number.

18006135840 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 18006135840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43557393600).

18006135840 is an abundant number, since it is smaller than the sum of its proper divisors (69108651360).

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

18006135840 is a wasteful number, since it uses less digits than its factorization.

18006135840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116 (or 84 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The spelling of 18006135840 in words is "eighteen billion, six million, one hundred thirty-five thousand, eight hundred forty".