18117216435540 has 48 divisors (see below), whose sum is σ = 51907931748288. Its totient is φ = 4718902884864.

The previous prime is 18117216435529. The next prime is 18117216435547. The reversal of 18117216435540 is 4553461271181.

It is a self number, because there is not a number n which added to its sum of digits gives 18117216435540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18117216435547) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3511085877 + ... + 3511091036.

It is an arithmetic number, because the mean of its divisors is an integer number (1081415244756).

Almost surely, 2^{18117216435540} is an apocalyptic number.

18117216435540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18117216435540 is an abundant number, since it is smaller than the sum of its proper divisors (33790715312748).

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

18117216435540 is a wasteful number, since it uses less digits than its factorization.

18117216435540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7022176968 (or 7022176966 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 48.

The spelling of 18117216435540 in words is "eighteen trillion, one hundred seventeen billion, two hundred sixteen million, four hundred thirty-five thousand, five hundred forty".