216869 has 4 divisors (see below), whose sum is σ = 229644. Its totient is φ = 204096.

The previous prime is 216859. The next prime is 216877. The reversal of 216869 is 968612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 148225 + 68644 = 385^2 + 262^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216869 is a prime.

It is a super-2 number, since 2×216869² = 94064326322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 6362 + ... + 6395.

It is an arithmetic number, because the mean of its divisors is an integer number (57411).

2²¹⁶⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

216869 is a deficient number, since it is larger than the sum of its proper divisors (12775).

216869 is a wasteful number, since it uses less digits than its factorization.

216869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12774.

The product of its digits is 5184, while the sum is 32.

The square root of 216869 is about 465.6919582728. The cubic root of 216869 is about 60.0803552987.

The spelling of 216869 in words is "two hundred sixteen thousand, eight hundred sixty-nine".