216623 has 8 divisors (see below), whose sum is σ = 241920. Its totient is φ = 192280.

The previous prime is 216617. The next prime is 216641. The reversal of 216623 is 326612.

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

It is not a de Polignac number, because 216623 - 2⁴ = 216607 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 216595 and 216604.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 216623.

It is not an unprimeable number, because it can be changed into a prime (216653) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 308 + ... + 726.

It is an arithmetic number, because the mean of its divisors is an integer number (30240).

2²¹⁶⁶²³ is an apocalyptic number.

216623 is a deficient number, since it is larger than the sum of its proper divisors (25297).

216623 is a wasteful number, since it uses less digits than its factorization.

216623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477.

The product of its digits is 432, while the sum is 20.

The square root of 216623 is about 465.4277602378. The cubic root of 216623 is about 60.0576298142.

The spelling of 216623 in words is "two hundred sixteen thousand, six hundred twenty-three".