216126161 has 2 divisors, whose sum is σ = 216126162. Its totient is φ = 216126160.

The previous prime is 216126137. The next prime is 216126191. The reversal of 216126161 is 161621612.

216126161 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., 174768400 + 41357761 = 13220^2 + 6431^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216126161 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 216126161.

It is not a weakly prime, because it can be changed into another prime (216126191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108063080 + 108063081.

It is an arithmetic number, because the mean of its divisors is an integer number (108063081).

Almost surely, 2^216126161 is an apocalyptic number.

It is an amenable number.

216126161 is a deficient number, since it is larger than the sum of its proper divisors (1).

216126161 is an equidigital number, since it uses as much as digits as its factorization.

216126161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 26.

The square root of 216126161 is about 14701.2299145344. The cubic root of 216126161 is about 600.1167930049.

Adding to 216126161 its reverse (161621612), we get a palindrome (377747773).

The spelling of 216126161 in words is "two hundred sixteen million, one hundred twenty-six thousand, one hundred sixty-one".