216889 has 4 divisors (see below), whose sum is σ = 219024. Its totient is φ = 214756.

The previous prime is 216877. The next prime is 216899. The reversal of 216889 is 988612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 216889 - 2⁷ = 216761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 907 + ... + 1120.

It is an arithmetic number, because the mean of its divisors is an integer number (54756).

2²¹⁶⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

216889 is a deficient number, since it is larger than the sum of its proper divisors (2135).

216889 is a wasteful number, since it uses less digits than its factorization.

216889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2134.

The product of its digits is 6912, while the sum is 34.

The square root of 216889 is about 465.7134311999. The cubic root of 216889 is about 60.0822021435.

The spelling of 216889 in words is "two hundred sixteen thousand, eight hundred eighty-nine".