217817718712 has 64 divisors (see below), whose sum is σ = 452794406400. Its totient is φ = 97405136640.

The previous prime is 217817718707. The next prime is 217817718737.

217817718712 is nontrivially palindromic in base 10.

217817718712 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 217817718712.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1683268 + ... + 1808044.

It is an arithmetic number, because the mean of its divisors is an integer number (7074912600).

Almost surely, 2^217817718712 is an apocalyptic number.

217817718712 is a gapful number since it is divisible by the number (22) 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 217817718712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (226397203200).

217817718712 is an abundant number, since it is smaller than the sum of its proper divisors (234976687688).

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

217817718712 is a wasteful number, since it uses less digits than its factorization.

217817718712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125116 (or 125112 counting only the distinct ones).

The product of its digits is 614656, while the sum is 52.

The spelling of 217817718712 in words is "two hundred seventeen billion, eight hundred seventeen million, seven hundred eighteen thousand, seven hundred twelve".