18117181440 has 240 divisors, whose sum is σ = 64422543360. Its totient is φ = 4830658560.

The previous prime is 18117181421. The next prime is 18117181463. The reversal of 18117181440 is 4418171181.

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

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 = 18117181395 and 18117181404.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2207745 + ... + 2215935.

It is an arithmetic number, because the mean of its divisors is an integer number (268427264).

Almost surely, 2^18117181440 is an apocalyptic number.

18117181440 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 18117181440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32211271680).

18117181440 is an abundant number, since it is smaller than the sum of its proper divisors (46305361920).

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

18117181440 is an frugal number, since it uses more digits than its factorization.

18117181440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8233 (or 8201 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 36.

The spelling of 18117181440 in words is "eighteen billion, one hundred seventeen million, one hundred eighty-one thousand, four hundred forty".