18440356168 has 64 divisors (see below), whose sum is σ = 38903639040. Its totient is φ = 8130549504.

The previous prime is 18440356163. The next prime is 18440356223. The reversal of 18440356168 is 86165304481.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is not an unprimeable number, because it can be changed into a prime (18440356163) 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 15 ways as a sum of consecutive naturals, for example, 2059830 + ... + 2068762.

It is an arithmetic number, because the mean of its divisors is an integer number (607869360).

Almost surely, 2^18440356168 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18440356168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19451819520).

18440356168 is an abundant number, since it is smaller than the sum of its proper divisors (20463282872).

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

18440356168 is a wasteful number, since it uses less digits than its factorization.

18440356168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9838 (or 9834 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 46.

The spelling of 18440356168 in words is "eighteen billion, four hundred forty million, three hundred fifty-six thousand, one hundred sixty-eight".