216864679 has 2 divisors, whose sum is σ = 216864680. Its totient is φ = 216864678.

The previous prime is 216864673. The next prime is 216864691. The reversal of 216864679 is 976468612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 216864679 - 2³ = 216864671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216864671) 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, 108432339 + 108432340.

It is an arithmetic number, because the mean of its divisors is an integer number (108432340).

Almost surely, 2^216864679 is an apocalyptic number.

216864679 is a deficient number, since it is larger than the sum of its proper divisors (1).

216864679 is an equidigital number, since it uses as much as digits as its factorization.

216864679 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 870912, while the sum is 49.

The square root of 216864679 is about 14726.3260523458. The cubic root of 216864679 is about 600.7995627295.

The spelling of 216864679 in words is "two hundred sixteen million, eight hundred sixty-four thousand, six hundred seventy-nine".