216688191440939 has 4 divisors (see below), whose sum is σ = 216688277603256. Its totient is φ = 216688105278624.

The previous prime is 216688191440921. The next prime is 216688191440983. The reversal of 216688191440939 is 939044191886612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216688191440939 - 2²⁰ = 216688190392363 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216688191440909) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39191789 + ... + 44377614.

It is an arithmetic number, because the mean of its divisors is an integer number (54172069400814).

Almost surely, 2^{216688191440939} is an apocalyptic number.

216688191440939 is a deficient number, since it is larger than the sum of its proper divisors (86162317).

216688191440939 is an equidigital number, since it uses as much as digits as its factorization.

216688191440939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86162316.

The product of its (nonzero) digits is 161243136, while the sum is 71.

The spelling of 216688191440939 in words is "two hundred sixteen trillion, six hundred eighty-eight billion, one hundred ninety-one million, four hundred forty thousand, nine hundred thirty-nine".