217011161 has 2 divisors, whose sum is σ = 217011162. Its totient is φ = 217011160.

The previous prime is 217011139. The next prime is 217011181. The reversal of 217011161 is 161110712.

It is a happy number.

It is an a-pointer prime, because the next prime (217011181) can be obtained adding 217011161 to its sum of digits (20).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 197262025 + 19749136 = 14045^2 + 4444^2 .

It is a cyclic number.

It is not a de Polignac number, because 217011161 - 2¹⁴ = 216994777 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (217011121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108505580 + 108505581.

It is an arithmetic number, because the mean of its divisors is an integer number (108505581).

Almost surely, 2^217011161 is an apocalyptic number.

It is an amenable number.

217011161 is a deficient number, since it is larger than the sum of its proper divisors (1).

217011161 is an equidigital number, since it uses as much as digits as its factorization.

217011161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84, while the sum is 20.

The square root of 217011161 is about 14731.2986868097. The cubic root of 217011161 is about 600.9348030011.

Adding to 217011161 its reverse (161110712), we get a palindrome (378121873).

It can be divided in two parts, 2170 and 11161, that added together give a palindrome (13331).

The spelling of 217011161 in words is "two hundred seventeen million, eleven thousand, one hundred sixty-one".