216304009 has 2 divisors, whose sum is σ = 216304010. Its totient is φ = 216304008.

The previous prime is 216303991. The next prime is 216304013. The reversal of 216304009 is 900403612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 213978384 + 2325625 = 14628^2 + 1525^2 .

It is a cyclic number.

It is not a de Polignac number, because 216304009 - 2⁷ = 216303881 is a prime.

It is not a weakly prime, because it can be changed into another prime (216301009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108152004 + 108152005.

It is an arithmetic number, because the mean of its divisors is an integer number (108152005).

Almost surely, 2^216304009 is an apocalyptic number.

It is an amenable number.

216304009 is a deficient number, since it is larger than the sum of its proper divisors (1).

216304009 is an equidigital number, since it uses as much as digits as its factorization.

216304009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 216304009 is about 14707.2774162997. The cubic root of 216304009 is about 600.2813578571.

The spelling of 216304009 in words is "two hundred sixteen million, three hundred four thousand, nine".