216616693 has 2 divisors, whose sum is σ = 216616694. Its totient is φ = 216616692.

The previous prime is 216616679. The next prime is 216616723. The reversal of 216616693 is 396616612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 207417604 + 9199089 = 14402^2 + 3033^2 .

It is a cyclic number.

It is not a de Polignac number, because 216616693 - 2⁹ = 216616181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216616613) 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, 108308346 + 108308347.

It is an arithmetic number, because the mean of its divisors is an integer number (108308347).

Almost surely, 2^216616693 is an apocalyptic number.

It is an amenable number.

216616693 is a deficient number, since it is larger than the sum of its proper divisors (1).

216616693 is an equidigital number, since it uses as much as digits as its factorization.

216616693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69984, while the sum is 40.

The square root of 216616693 is about 14717.9038249338. The cubic root of 216616693 is about 600.5704694728.

The spelling of 216616693 in words is "two hundred sixteen million, six hundred sixteen thousand, six hundred ninety-three".