216447 has 16 divisors (see below), whose sum is σ = 360192. Its totient is φ = 112320.

The previous prime is 216431. The next prime is 216451. The reversal of 216447 is 744612.

It is not a de Polignac number, because 216447 - 2⁴ = 216431 is a prime.

216447 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 238 + ... + 699.

It is an arithmetic number, because the mean of its divisors is an integer number (22512).

2²¹⁶⁴⁴⁷ is an apocalyptic number.

216447 is a deficient number, since it is larger than the sum of its proper divisors (143745).

216447 is a wasteful number, since it uses less digits than its factorization.

216447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 958.

The product of its digits is 1344, while the sum is 24.

The square root of 216447 is about 465.2386484376. The cubic root of 216447 is about 60.0413603710.

It can be divided in two parts, 2164 and 47, that added together give a triangular number (2211 = T₆₆).

The spelling of 216447 in words is "two hundred sixteen thousand, four hundred forty-seven".