216842 has 4 divisors (see below), whose sum is σ = 325266. Its totient is φ = 108420.

The previous prime is 216841. The next prime is 216851. The reversal of 216842 is 248612.

216842 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 177241 + 39601 = 421^2 + 199^2 .

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (216841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54209 + ... + 54212.

2²¹⁶⁸⁴² is an apocalyptic number.

216842 is a deficient number, since it is larger than the sum of its proper divisors (108424).

216842 is a wasteful number, since it uses less digits than its factorization.

216842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108423.

The product of its digits is 768, while the sum is 23.

The square root of 216842 is about 465.6629682506. The cubic root of 216842 is about 60.0778618781.

The spelling of 216842 in words is "two hundred sixteen thousand, eight hundred forty-two".