216889549 has 12 divisors (see below), whose sum is σ = 227546172. Its totient is φ = 206606400.

The previous prime is 216889531. The next prime is 216889559. The reversal of 216889549 is 945988612.

It can be written as a sum of positive squares in 2 ways, for example, as 55980324 + 160909225 = 7482^2 + 12685^2 .

It is not a de Polignac number, because 216889549 - 2⁹ = 216889037 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 216889496 and 216889505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216889559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 74379 + ... + 77239.

It is an arithmetic number, because the mean of its divisors is an integer number (18962181).

Almost surely, 2^216889549 is an apocalyptic number.

It is an amenable number.

216889549 is a deficient number, since it is larger than the sum of its proper divisors (10656623).

216889549 is an equidigital number, since it uses as much as digits as its factorization.

216889549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2988 (or 2945 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 52.

The square root of 216889549 is about 14727.1704342688. The cubic root of 216889549 is about 600.8225283780.

The spelling of 216889549 in words is "two hundred sixteen million, eight hundred eighty-nine thousand, five hundred forty-nine".