216428929 has 2 divisors, whose sum is σ = 216428930. Its totient is φ = 216428928.

The previous prime is 216428909. The next prime is 216428951. The reversal of 216428929 is 929824612.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 193961329 + 22467600 = 13927^2 + 4740^2 .

It is a cyclic number.

It is not a de Polignac number, because 216428929 - 2¹⁵ = 216396161 is a prime.

It is not a weakly prime, because it can be changed into another prime (216428909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108214464 + 108214465.

It is an arithmetic number, because the mean of its divisors is an integer number (108214465).

Almost surely, 2^216428929 is an apocalyptic number.

It is an amenable number.

216428929 is a deficient number, since it is larger than the sum of its proper divisors (1).

216428929 is an equidigital number, since it uses as much as digits as its factorization.

216428929 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 124416, while the sum is 43.

The square root of 216428929 is about 14711.5236804350. The cubic root of 216428929 is about 600.3968938823.

The spelling of 216428929 in words is "two hundred sixteen million, four hundred twenty-eight thousand, nine hundred twenty-nine".