71205161 has 2 divisors, whose sum is σ = 71205162. Its totient is φ = 71205160.

The previous prime is 71205157. The next prime is 71205187. The reversal of 71205161 is 16150217.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42250000 + 28955161 = 6500^2 + 5381^2 .

It is an emirp because it is prime and its reverse (16150217) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71205161 - 2² = 71205157 is a prime.

It is not a weakly prime, because it can be changed into another prime (71207161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35602580 + 35602581.

It is an arithmetic number, because the mean of its divisors is an integer number (35602581).

Almost surely, 2^71205161 is an apocalyptic number.

It is an amenable number.

71205161 is a deficient number, since it is larger than the sum of its proper divisors (1).

71205161 is an equidigital number, since it uses as much as digits as its factorization.

71205161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 71205161 is about 8438.3150569293. The cubic root of 71205161 is about 414.4802337931.

Adding to 71205161 its reverse (16150217), we get a palindrome (87355378).

The spelling of 71205161 in words is "seventy-one million, two hundred five thousand, one hundred sixty-one".