216442 has 8 divisors (see below), whose sum is σ = 335232. Its totient is φ = 104700.

The previous prime is 216431. The next prime is 216451. The reversal of 216442 is 244612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

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, 1684 + ... + 1807.

It is an arithmetic number, because the mean of its divisors is an integer number (41904).

2²¹⁶⁴⁴² is an apocalyptic number.

216442 is a deficient number, since it is larger than the sum of its proper divisors (118790).

216442 is a wasteful number, since it uses less digits than its factorization.

216442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3524.

The product of its digits is 384, while the sum is 19.

The square root of 216442 is about 465.2332748203. The cubic root of 216442 is about 60.0408980421.

The spelling of 216442 in words is "two hundred sixteen thousand, four hundred forty-two".