216322231 has 2 divisors, whose sum is σ = 216322232. Its totient is φ = 216322230.

The previous prime is 216322219. The next prime is 216322237. The reversal of 216322231 is 132223612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 216322231 - 2¹¹ = 216320183 is a prime.

It is a super-2 number, since 2×216322231² = 93590615249634722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216322237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108161115 + 108161116.

It is an arithmetic number, because the mean of its divisors is an integer number (108161116).

Almost surely, 2^216322231 is an apocalyptic number.

216322231 is a deficient number, since it is larger than the sum of its proper divisors (1).

216322231 is an equidigital number, since it uses as much as digits as its factorization.

216322231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 22.

The square root of 216322231 is about 14707.8968924860. The cubic root of 216322231 is about 600.2982137934.

Adding to 216322231 its reverse (132223612), we get a palindrome (348545843).

The spelling of 216322231 in words is "two hundred sixteen million, three hundred twenty-two thousand, two hundred thirty-one".