216863 has 4 divisors (see below), whose sum is σ = 218040. Its totient is φ = 215688.

The previous prime is 216859. The next prime is 216877. The reversal of 216863 is 368612.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 216863 - 2² = 216859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216803) 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, 245 + ... + 702.

It is an arithmetic number, because the mean of its divisors is an integer number (54510).

2²¹⁶⁸⁶³ is an apocalyptic number.

216863 is a deficient number, since it is larger than the sum of its proper divisors (1177).

216863 is an equidigital number, since it uses as much as digits as its factorization.

216863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1176.

The product of its digits is 1728, while the sum is 26.

The square root of 216863 is about 465.6855162017. The cubic root of 216863 is about 60.0798012231.

The spelling of 216863 in words is "two hundred sixteen thousand, eight hundred sixty-three".