216838118691 has 28 divisors (see below), whose sum is σ = 325517242512. Its totient is φ = 144376980336.

The previous prime is 216838118683. The next prime is 216838118729. The reversal of 216838118691 is 196811838612.

It is a happy number.

216838118691 is a `hidden beast` number, since 2 + 168 + 381 + 18 + 6 + 91 = 666.

It is not a de Polignac number, because 216838118691 - 2³ = 216838118683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (216838118891) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 394410 + ... + 767616.

It is an arithmetic number, because the mean of its divisors is an integer number (11625615804).

Almost surely, 2^216838118691 is an apocalyptic number.

216838118691 is a deficient number, since it is larger than the sum of its proper divisors (108679123821).

216838118691 is an frugal number, since it uses more digits than its factorization.

216838118691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374022 (or 374007 counting only the distinct ones).

The product of its digits is 995328, while the sum is 54.

The spelling of 216838118691 in words is "two hundred sixteen billion, eight hundred thirty-eight million, one hundred eighteen thousand, six hundred ninety-one".