71057081 has 2 divisors, whose sum is σ = 71057082. Its totient is φ = 71057080.

The previous prime is 71057071. The next prime is 71057083. The reversal of 71057081 is 18075017.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70291456 + 765625 = 8384^2 + 875^2 .

It is an emirp because it is prime and its reverse (18075017) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71057081 is a prime.

It is a super-2 number, since 2×71057081² = 10098217520481122, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 71057083, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (71057083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35528540 + 35528541.

It is an arithmetic number, because the mean of its divisors is an integer number (35528541).

Almost surely, 2^71057081 is an apocalyptic number.

It is an amenable number.

71057081 is a deficient number, since it is larger than the sum of its proper divisors (1).

71057081 is an equidigital number, since it uses as much as digits as its factorization.

71057081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1960, while the sum is 29.

The square root of 71057081 is about 8429.5362268633. The cubic root of 71057081 is about 414.1927133012.

The spelling of 71057081 in words is "seventy-one million, fifty-seven thousand, eighty-one".