2181660116817 has 8 divisors (see below), whose sum is σ = 2987498538496. Its totient is φ = 1415130886512.

The previous prime is 2181660116789. The next prime is 2181660116819. The reversal of 2181660116817 is 7186110661812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2181660116817 - 2⁷ = 2181660116689 is a prime.

It is a super-2 number, since 2×2181660116817² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2181660116819) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9827297713 + ... + 9827297934.

It is an arithmetic number, because the mean of its divisors is an integer number (373437317312).

Almost surely, 2^{2181660116817} is an apocalyptic number.

It is an amenable number.

2181660116817 is a deficient number, since it is larger than the sum of its proper divisors (805838421679).

2181660116817 is a wasteful number, since it uses less digits than its factorization.

2181660116817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19654595687.

The product of its (nonzero) digits is 193536, while the sum is 48.

The spelling of 2181660116817 in words is "two trillion, one hundred eighty-one billion, six hundred sixty million, one hundred sixteen thousand, eight hundred seventeen".