216430999 has 2 divisors, whose sum is σ = 216431000. Its totient is φ = 216430998.

The previous prime is 216430979. The next prime is 216431003. The reversal of 216430999 is 999034612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 216430999 - 2⁵ = 216430967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216430979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108215499 + 108215500.

It is an arithmetic number, because the mean of its divisors is an integer number (108215500).

Almost surely, 2^216430999 is an apocalyptic number.

216430999 is a deficient number, since it is larger than the sum of its proper divisors (1).

216430999 is an equidigital number, since it uses as much as digits as its factorization.

216430999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 104976, while the sum is 43.

The square root of 216430999 is about 14711.5940332787. The cubic root of 216430999 is about 600.3988080097.

The spelling of 216430999 in words is "two hundred sixteen million, four hundred thirty thousand, nine hundred ninety-nine".