216819 has 6 divisors (see below), whose sum is σ = 313196. Its totient is φ = 144540.

The previous prime is 216803. The next prime is 216829. The reversal of 216819 is 918612.

It is not a de Polignac number, because 216819 - 2⁴ = 216803 is a prime.

It is a super-2 number, since 2×216819² = 94020957522, which contains 22 as substring.

It is a Duffinian number.

216819 is a lucky number.

It is a plaindrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 216792 and 216801.

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

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12037 + ... + 12054.

2²¹⁶⁸¹⁹ is an apocalyptic number.

216819 is a deficient number, since it is larger than the sum of its proper divisors (96377).

216819 is a wasteful number, since it uses less digits than its factorization.

216819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24097 (or 24094 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 216819 is about 465.6382716229. The cubic root of 216819 is about 60.0757376898.

It can be divided in two parts, 2168 and 19, that added together give a 7-th power (2187 = 3⁷).

The spelling of 216819 in words is "two hundred sixteen thousand, eight hundred nineteen".