216507161693 has 2 divisors, whose sum is σ = 216507161694. Its totient is φ = 216507161692.

The previous prime is 216507161671. The next prime is 216507161723. The reversal of 216507161693 is 396161705612.

216507161693 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 185143460089 + 31363701604 = 430283^2 + 177098^2 .

It is a cyclic number.

It is not a de Polignac number, because 216507161693 - 2¹² = 216507157597 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216507163693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108253580846 + 108253580847.

It is an arithmetic number, because the mean of its divisors is an integer number (108253580847).

Almost surely, 2^216507161693 is an apocalyptic number.

It is an amenable number.

216507161693 is a deficient number, since it is larger than the sum of its proper divisors (1).

216507161693 is an equidigital number, since it uses as much as digits as its factorization.

216507161693 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 408240, while the sum is 47.

The spelling of 216507161693 in words is "two hundred sixteen billion, five hundred seven million, one hundred sixty-one thousand, six hundred ninety-three".