216959549 has 2 divisors, whose sum is σ = 216959550. Its totient is φ = 216959548.

The previous prime is 216959497. The next prime is 216959569. The reversal of 216959549 is 945959612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 141443449 + 75516100 = 11893^2 + 8690^2 .

It is a cyclic number.

It is not a de Polignac number, because 216959549 - 2²⁰ = 215910973 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 216959497 and 216959506.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216959569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108479774 + 108479775.

It is an arithmetic number, because the mean of its divisors is an integer number (108479775).

Almost surely, 2^216959549 is an apocalyptic number.

It is an amenable number.

216959549 is a deficient number, since it is larger than the sum of its proper divisors (1).

216959549 is an equidigital number, since it uses as much as digits as its factorization.

216959549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 874800, while the sum is 50.

The square root of 216959549 is about 14729.5468022611. The cubic root of 216959549 is about 600.8871588983.

The spelling of 216959549 in words is "two hundred sixteen million, nine hundred fifty-nine thousand, five hundred forty-nine".