216099 has 12 divisors (see below), whose sum is σ = 336336. Its totient is φ = 132912.

The previous prime is 216091. The next prime is 216103. The reversal of 216099 is 990612.

It is a happy number.

It is not a de Polignac number, because 216099 - 2³ = 216091 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 216099.

It is not an unprimeable number, because it can be changed into a prime (216091) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 807 + ... + 1040.

It is an arithmetic number, because the mean of its divisors is an integer number (28028).

216099 is a Friedman number, since it can be written as 99+60^(2+1), using all its digits and the basic arithmetic operations.

2²¹⁶⁰⁹⁹ is an apocalyptic number.

216099 is a deficient number, since it is larger than the sum of its proper divisors (120237).

216099 is a wasteful number, since it uses less digits than its factorization.

216099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1866 (or 1863 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 216099 is about 464.8644963858. The cubic root of 216099 is about 60.0091652666.

It can be divided in two parts, 21609 and 9, that multiplied together give a 4-th power (194481 = 21⁴).

The spelling of 216099 in words is "two hundred sixteen thousand, ninety-nine".