216911 has 2 divisors, whose sum is σ = 216912. Its totient is φ = 216910.

The previous prime is 216901. The next prime is 216917. The reversal of 216911 is 119612.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216911 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108455 + 108456.

It is an arithmetic number, because the mean of its divisors is an integer number (108456).

2²¹⁶⁹¹¹ is an apocalyptic number.

216911 is a deficient number, since it is larger than the sum of its proper divisors (1).

216911 is an equidigital number, since it uses as much as digits as its factorization.

216911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108, while the sum is 20.

The square root of 216911 is about 465.7370502762. The cubic root of 216911 is about 60.0842335417.

The spelling of 216911 in words is "two hundred sixteen thousand, nine hundred eleven".