216801 has 24 divisors (see below), whose sum is σ = 360360. Its totient is φ = 124416.

The previous prime is 216791. The next prime is 216803. The reversal of 216801 is 108612.

216801 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 40401 + 176400 = 201^2 + 420^2 .

It is not a de Polignac number, because 216801 - 2⁹ = 216289 is a prime.

216801 is strictly pandigital in base 7.

It is not an unprimeable number, because it can be changed into a prime (216803) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1935 + ... + 2043.

It is an arithmetic number, because the mean of its divisors is an integer number (15015).

2²¹⁶⁸⁰¹ is an apocalyptic number.

It is an amenable number.

216801 is a deficient number, since it is larger than the sum of its proper divisors (143559).

216801 is a wasteful number, since it uses less digits than its factorization.

216801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 216801 is about 465.6189429136. The cubic root of 216801 is about 60.0740751768.

The spelling of 216801 in words is "two hundred sixteen thousand, eight hundred one".