217601161 has 2 divisors, whose sum is σ = 217601162. Its totient is φ = 217601160.

The previous prime is 217601099. The next prime is 217601177. The reversal of 217601161 is 161106712.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122655625 + 94945536 = 11075^2 + 9744^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-217601161 is a prime.

It is not a weakly prime, because it can be changed into another prime (217601191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108800580 + 108800581.

It is an arithmetic number, because the mean of its divisors is an integer number (108800581).

Almost surely, 2^217601161 is an apocalyptic number.

It is an amenable number.

217601161 is a deficient number, since it is larger than the sum of its proper divisors (1).

217601161 is an equidigital number, since it uses as much as digits as its factorization.

217601161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 25.

The square root of 217601161 is about 14751.3104841570. The cubic root of 217601161 is about 601.4789082040.

Adding to 217601161 its reverse (161106712), we get a palindrome (378707873).

The spelling of 217601161 in words is "two hundred seventeen million, six hundred one thousand, one hundred sixty-one".