216185568081 has 12 divisors (see below), whose sum is σ = 335308228272. Its totient is φ = 123534610248.

The previous prime is 216185568073. The next prime is 216185568139. The reversal of 216185568081 is 180865581612.

It is not a de Polignac number, because 216185568081 - 2³ = 216185568073 is a prime.

It is a super-2 number, since 2×216185568081² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (216185566081) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 735324915 + ... + 735325208.

It is an arithmetic number, because the mean of its divisors is an integer number (27942352356).

Almost surely, 2^216185568081 is an apocalyptic number.

216185568081 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

216185568081 is a deficient number, since it is larger than the sum of its proper divisors (119122660191).

216185568081 is a wasteful number, since it uses less digits than its factorization.

216185568081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1470650140 (or 1470650133 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 51.

The spelling of 216185568081 in words is "two hundred sixteen billion, one hundred eighty-five million, five hundred sixty-eight thousand, eighty-one".