18321171878016 has 320 divisors, whose sum is σ = 62361695119680. Its totient is φ = 5230494922752.

The previous prime is 18321171877997. The next prime is 18321171878017. The reversal of 18321171878016 is 61087817112381.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (18321171878017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 92580711 + ... + 92778393.

It is an arithmetic number, because the mean of its divisors is an integer number (194880297249).

Almost surely, 2^{18321171878016} is an apocalyptic number.

18321171878016 is a gapful number since it is divisible by the number (16) 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 18321171878016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31180847559840).

18321171878016 is an abundant number, since it is smaller than the sum of its proper divisors (44040523241664).

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

18321171878016 is a wasteful number, since it uses less digits than its factorization.

18321171878016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198993 (or 198972 counting only the distinct ones).

The product of its (nonzero) digits is 903168, while the sum is 54.

The spelling of 18321171878016 in words is "eighteen trillion, three hundred twenty-one billion, one hundred seventy-one million, eight hundred seventy-eight thousand, sixteen".