216243089 has 2 divisors, whose sum is σ = 216243090. Its totient is φ = 216243088.

The previous prime is 216243037. The next prime is 216243091. The reversal of 216243089 is 980342612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 210018064 + 6225025 = 14492^2 + 2495^2 .

It is a cyclic number.

It is not a de Polignac number, because 216243089 - 2⁸ = 216242833 is a prime.

It is a super-2 number, since 2×216243089² = 93522147080523842, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 216243091, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (216243019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108121544 + 108121545.

It is an arithmetic number, because the mean of its divisors is an integer number (108121545).

Almost surely, 2^216243089 is an apocalyptic number.

It is an amenable number.

216243089 is a deficient number, since it is larger than the sum of its proper divisors (1).

216243089 is an equidigital number, since it uses as much as digits as its factorization.

216243089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 216243089 is about 14705.2061869258. The cubic root of 216243089 is about 600.2249980233.

The spelling of 216243089 in words is "two hundred sixteen million, two hundred forty-three thousand, eighty-nine".