71216261 has 2 divisors, whose sum is σ = 71216262. Its totient is φ = 71216260.

The previous prime is 71216251. The next prime is 71216263. The reversal of 71216261 is 16261217.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52562500 + 18653761 = 7250^2 + 4319^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71216261 is a prime.

Together with 71216263, it forms a pair of twin primes.

It is a Chen prime.

It is a zygodrome in base 3.

It is a self number, because there is not a number n which added to its sum of digits gives 71216261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71216263) 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, 35608130 + 35608131.

It is an arithmetic number, because the mean of its divisors is an integer number (35608131).

Almost surely, 2^71216261 is an apocalyptic number.

It is an amenable number.

71216261 is a deficient number, since it is larger than the sum of its proper divisors (1).

71216261 is an equidigital number, since it uses as much as digits as its factorization.

71216261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1008, while the sum is 26.

The square root of 71216261 is about 8438.9727455420. The cubic root of 71216261 is about 414.5017701138.

Adding to 71216261 its reverse (16261217), we get a palindrome (87477478).

The spelling of 71216261 in words is "seventy-one million, two hundred sixteen thousand, two hundred sixty-one".